CAVATAK - intralesional therapy derived from the coxsackievirus

Many intralesional therapies, medicine that is injected directly into a tumor, have been found to have some success in melanoma.  We have learned that, at times, they can not only kill the tumor into which they are injected, but "by-stander" tumors as well. First tried in 1975 with the BCG vaccine, things as disparate as IL2, Allovectin-7 (a DNA mixture), T-VEC/OncoVEX (derived from the herpes virus), L19, PV-10 (from the dye Rose Bengal), GM-CSF, and CAVATAK (derived from the coxsackievirus) have been used.  Additionally, some of these intralesionals have been tested combined with systemic immunotherapy.  The idea being that one could prime an immune response by injecting a tumor with an oncolytic virus, eliciting a T-cell influx, and follow with systemic immunotherapy.

Here's some background on the process:  Intralesional therapy for melanoma
Here is a brief review as well as reports from a study where T-VEC was combined with pembro, another with T-VEC and ipi, ipi given with IL2, as well as a report from the CALM study [don't you love their names????!!!] in which the coxsackievirus (CAVATAK) was administered singly:  From ASCO 2015: intralesional therapy for melanoma
Here's specifics on T-VEC:   Good News - local and systemic response to T-VEC
Here's the low-down on PV-10:  ASCO 2014: Rose Bengal (PV-10) with additional links
T-VEC combined with ipi: Pick your poison: Weber and Agarwala
     "When ipi is combined with T-VEC (an intralesional therapy) you get a better response rate...about 55% combined complete and partial responses....than with either drug alone."

Now....in truth....I am putting this together for my dear friend, Josh....so I am going to focus on an option he is looking at....CAVATAK with ipi.

Here is info from the CAVATAK only, CALM trial:

 Final data from CALM: A phase II study of Coxsackievirus A21 (CVA21) oncolytic virus immunotherapy in patients with advanced melanoma.  ASCO - J Clin Oncol 33, 2015.  Andtbacka, Curti, Kaufman, Daniels, et al.

"CVA21 is a novel bio-selected oncolytic and immunotherapeutic strain of Coxsackievirus A21.  Intratumal injection initiates preferential tumor cell infection, cell lysis [death] and enhancement of a systemic anti-tumor immune response.  The CALM study looked at 57 patients with treated or untreated, unresectable Stage IIIC-IV melanoma.  Patients were given injections on study days 1, 3, 5, 8, and 22, then every 3 weeks for a further 6 injections.  Patients showing immune-related progression-free survival or better at 6 months were eligible for 9 additional injections.  RESULTS:  21 of 57 (38%) patients displayed progression free survival at 6 months with median PFS of 4.2 months.  Overall response rate was 28% (16 of 57) with a more than 6 month durable response rate of 19% (11 of 57).  Median time to response was 2.8 months, 1 year survival rate was 75% (43 of 57 patients).  At more than 16 months, median duration of response in responders and median overall survival for all patients was not yet reached.  Most common side effects = Grade 1 fatigue, chills, local injection site reaction, and fever.  No grade 3 or 4 reactions.  Further studies with CVA21 in combination with other immunotherapies are in process."

And this link/synopsis of Weber's "What's new in 2016" talk...discusses what's coming and recent in melanoma care as well as CALM results:  Immunology update webinar for melanoma
Within...this blurb is included:  

Intralesional Immunotherapy With Oncolytic Coxsackievirus A21 (CVA21) 
 Final response and safety data of the open-label, multicenter phaseII CALM (CAVATAK in Late-stageMelanoma) study of intratumoral CVA21 in 57 patients with unresectable stage IIIC/IV melanoma.    The study met its primary endpoint.  22 of 57 (38.6%) evaluable patients with PFS at 6 months.    Median PFS of 4.2 mos.   ORR 28.1%; median TTR 2.8 mos.  1-year survival rate 75.4%.  Median OS and median DOR not reached (16.5 mos follow-up).  Most common AEs were grade 1 fatigue, chills, fever, and injection site reactions; no grade 3/4 AEs observed.  Looks like another promising intralesional therapy.  Will soon have phase 3 study.

A link to one other report:   Viralytics reports positive final results from cavatak phase 2 melanoma trial

Here is a link to:  Intratumoral CAVATAK and ipi trial
Apparently folks will get ipi at 3mg/kg 4 times.  You have to have an injectable tumor (per their criteria) and CAVATAK will be injected 4 specific times and then every three weeks for up to one year.  The study is a Phase 1 trial, sponsored by Viralytics and was started in late 2014. You can't have taken ipi for metastatic melanoma, but you can have taken it as an adjuvant as long as you did not experience a grade 3 toxicity.  Trial is recruiting in California, Oregon and Illinois.

CAVATAK is also being studied in bladder cancer and non-small-cell lung cancer.  There is also a study combining CAVATAK with pembro for melanoma.  Here's the link:  Intratumoral cavatak and pembro trial  Here folks will get CAVATAK injections at specific times up to 19 total injections into "at least one cutaneous, subcutaneous tumor or palpable lymph node amenable to intratumoral injection" and pembro infusions every 3 weeks up to 2 years. Exclusions include:  no corticosteriods, ocular or mucosal melanoma.  No prior anti-PD1 or PDL1.  Also sponsored by Viralytics, recruiting in New Jersey.

Guess that's about all I got.  I have always been a fan of intralesional therapy...telling B that if I ever recur...and have to have some sort of surgery...I was going to beg to have Rose Bengal and lord knows what else...just splashed around in there before they sew me up.  Those who know B can imagine the big blue eye roll that comment gets me....but there you go!!!  Love you, Josh!  - c

ASCO 2016: CAVATAK (intralesional treatment derived from the Coxsackievirus) Factors that improve response!

I recently posted this:  CAVATAK Intralesional therapy for melanoma

Here's what was posted at ASCO regarding factors that improved response....

Dynamics of tumor response in advanced melanoma patients treated with Coxsackievirus A21.  ASCO 2016. #9553.  J Clin Oncol 2016.  Andtbacka, Curti, Kaufman, et al.

Background: CAVATAK, an oncolytic immunotherapy, is a bio-selected oncolytic strain of Coxsackievirus A21 (CVA21). Intratumoral (IT) injection of CVA21 induces lytic tumor cell infection, up-regulation of immune checkpoint molecules and increased immune-cell infiltration. The Phase II CALM study investigated the efficacy and safety of IT CVA21 in 57 pts with advanced melanoma resulting in a confirmed ORR of 28.1% and DRR of 21.1%. The CALM extension study (13 pts) investigated CVA21 induced changes in immune cell infiltrates within the tumor-microenvironment (TME). We describe factors regarding the nature of clinical responses in 70 pts with stage IIIC-IV melanoma given IT CVA21. Methods: The association of prior lines of therapy, tumor pseudo-progression, baseline tumor burden (BTB) and levels of immune cell infiltrates in the TME were examined with regard to clinical response. Results: Responders on the CALM study (16/57 pts, 28.1%) displayed reductions in both injected and non-injected lesions, suggesting the generation of significant host anti-tumor responses. A comparable ORR was observed in pts administered prior immunotherapy, 29.0% (9/31) vs other tx 27.0% (7/26). Interestingly, 26.7% (4/15) and 40% (2/5) of pts previously treated with ipilimumab and talimogene laherparepvec, respectively, developed confirmed responses. Three pts (18.8%) exhibited pseudo-progression (irRECIST criteria) prior to response. BTB of the 57 pts in the CALM study was 3.9 cm. A BTB less than median was associated with: superior ORR (39.3 vs 17.2 %), superior DRR (35.7 vs 6.9 %), and greater OS. In the CALM extension study, CVA21 tx induced increases in immune cell infiltrates within the TME. In patients with responses, increases in CD8⁺ T-cells and PD-L1⁺ expression were observed in injected lesions. Reconstitution of immune cell infiltrates was observed in a number of CVA21 treated lesions from pts failing prior tx with immune-checkpoint blockade. Conclusions: IT administration of CVA21 can notably influence the dynamics of the TME and generate systemic anti-tumor immune responses as evidenced by increases in immune cell infiltrates and widespread non-injected lesion responses. Clinical trial information: NCT01227551

These are small numbers, but...CAVATAK certainly changed the tumor-microenvironment, worked in treated and UN-treated lesions, previous treatment with ipi or T-VEC may make it work better, and as would be expected, folks with a lower tumor burden did better.  Pseudoprogression was also noted at times.

It seems reasonable to assume that combining CAVATAK with a systemic therapy (as noted in the prior post) should improve responses! -c

ASCO 2017: All things intralesional/intratumoral

I have long been a fan of intralesional (intratumoral...pick your nomenclature) therapy's potential. These are medications that are injected directly into superficial lesions...which researchers have found can make the injected tumors, as well as distant ones, GO AWAY!!! Additionally, it has long been supposed that if they were combined with systemic immunotherapy they would work even better.

In 2014 I wrote:  "Intralesional melanoma therapy (A procedure in which the "treatment" is directly injected into superficial tumors and in theory, not only does that tumor die, but "by stander" tumors at more distant sites die too!!!) was first recorded back in 1975.  A 75 year old male with 64 melanoma mets just below the skin, as well as junk in his lungs, had 17 superficial lesions injected with Bacille Calmette-Guerin over a period of 8 months. (BCG is a vaccine against some strains of tuberculosis, but does contain a weakened version of the bacteria itself within it.) In the end, all 17 tumors injected resolved and his pulmonary mets diminished by more than 50%!  However, enthusiasm for BCG as a melanoma treatment waned as patients in subsequent trials experienced anaphylactic reactions and death due to disseminated BCG, and randomized trials failed to replicate significant clinical benefit.

Later, intralesional therapy was tried using all sorts of things.  More recently Allovectin-7, OncoVEX, and PV-10 have demonstrated positive results, killing melanoma at the injected site and systemically.  

Today, three years later.... we now know that, unfortunately, Allovectin-7 (velimogen aliplasmid) did not work out and trials were ended by its manufacturer, Vical. However, we do have an additional intralesional: CAVATAK, derived from the Coxsackievirus (a frequent cause of the common cold) produced by Virolytics.   OncoVEX now also called Talimogene Laherparepvec (or T-vec, brand name Imlygic) engineered using the herpes virus and GM-CSF, developed originally by BioVex and now produced by Amgen who bought them out, is still in process. There is also PV-10 generated from Rose Bengal made by Provectus.  It has shown promise in studies I have previously posted and there is this blurb from Fortune magazine in 2016:

"Final results from an ongoing 225-patient melanoma trial of the experimental drug compared to chemotherapy are expected in early 2018. The hope is that the drug, known as PV-10, will prevent melanoma from progressing beyond Stage III, in which the disease has spread but not yet to other organs, and allow patients with more advanced cancer to live longer." 

From a 2016 study that paired PV-10 with radiation there was this:   "15 patients enrolled with 13 completing the radiotherapy component. Two patients had rapidly progressive distant disease following PV-10 injection. The mean age of patients was 69 years. With a median follow up duration of 19.3 months the overall response rate was 87% with 93% clinical benefit on an intent-to-treat basis. The mean time to best response was 3.8 months, mean duration of complete response (PFS) 12.2 months, overall loco regional progression rate 80% and melanoma specific survival 65.5 months.  Size of metastases (less than 10mm) predicted potential for lesion complete response. "

For whatever reason, perhaps due to the immaturity of the data, (In addition to the study referenced above, a study was started in 2016 combining PV-10 with pembro.) PV-10 did not make it to an ASCO presentation this year...not at least any I found. Here is a link to prior posts:  All things PV-10

*************************CAVATAK********************************

CAVATAK has been talked up for a while now.  Here are links to many posts:  All things CAVATAK  In a 2016 report where CAVATAK was used alone, this was reported:  "Responders on the CALM study (16/57 pts, 28.1%) displayed reductions in both injected and non-injected lesions, suggesting the generation of significant host anti-tumor responses. A comparable ORR was observed in pts administered prior immunotherapy, 29.0% (9/31) vs other tx 27.0% (7/26). Interestingly, 26.7% (4/15) and 40% (2/5) of pts previously treated with ipilimumab and talimogene laherparepvec, respectively, developed confirmed responses."

Here, CAVATAK is combined with ipi:

Activity of a novel immunotherapy combination of intralesional Coxsackievirus A21 and systemic ipilimumab in advanced melanoma patients previously treated with anti-PD1 blockade therapy.

ASCO 2017. J Clin Oncol 35, 2017. Curti, Richards, Hallmeyer, Faries, Andbacka, et al.

Background: CAVATAK is a novel bio-selected oncolytic and immunotherapeutic strain of Coxsackievirus A21 (CVA21) that when injected into melanoma lesions can increase immune-cell infiltration, up-regulation of γ-INF response and immune-checkpoint genes, including CD122, which may be a potential marker for enhanced anti-tumor activity by anti-CTLA-4 blockade. Intratumoral replication of CVA21 may act as a strong “immune-sequestration signal” to circulating activated T-cells following CTLA-4 blockade. A large unmet need exists for active therapies in melanoma patients (pts) following treatment (tx) with anti-PD1 therapies. We present in a Phase 1 study, the clinical activity of a CVA21/ ipilimumab (ipi) combination following anti–PD1 therapy in advanced melanoma pts. Methods: The Phase Ib MITCI study (NCT02307149) investigated the efficacy and safety of i.t. CVA21 and i.v. ipi in 26 pts with unresectable Stage IIIB/C-IVM1c melanoma with 13 pts previously treated with anti-PD1 therapies. Pts received up to 3 x 10⁸ TCID₅₀CVA21 i.t. on study days 1, 3, 5, 8 and 22, and then q3w for a further 6 series of injections. Ipi (3 mg/kg) q3w was given as 4 i.v. infusions starting at Day 22. Results: Analysis of the prior anti–PD1 treated pts (n=13) revealed that the combination tx was generally well-tolerated with one case of Gr 3 ipi-related liver toxicity observed. Of the tx population, 54% (7/13) had received prior ipi tx in addition to anti-PD1, 85% (11/13) of pts were stage IV M1b/c, with the median time between the last anti-PD1 and first CVA21 and ipi doses being 5.7 and 8.7 weeks, respectively. The mean number of prior systemic therapies including anti-PD1 tx was 2.6. For all pts completing at least the first investigator response assessment (irWHO criteria at Day 106) we observed a confirmed BORR of 38.0% (3/8) and a DCR (CR+PR+SD) of 88% (7/8). Conclusions: Intratumoral CVA21 + ipilimumab treatment in anti–PD1 treated pts has displayed promising clinical activity together with low adverse toxicity and as such this regimen may represent a valuable tx option for pts that have been administered previous lines of immune checkpoint therapy. 

Here 26 patients (Stage III and IV) - 13 with prior anti-PD-1, had lesions injected with CAVATAK and ipi (3mg/kg) was given 4 times IV.  Best ORR = 38% with a total response rate of 88% when complete response, partial response and stable disease were combined.

**********************************T-VEC*********************

ASCO 2016 began to report the results of T-VEC combined with Pembro, reporting:  "Of the 21 pts enrolled from Dec 2014 – Mar 2015, 48% had IIIB-IVM1a, 52% IVM1b/c, 76% HSV-1+, and 19% BRAFmut+. Median follow-up at data cut was 33 w. All pts received at least one dose of T-VEC+pembro. Tx-related AEs occurred in all pts: 33% G3/4, and no G5. Most common AEs were fatigue (62%), pyrexia (52%), and chills (48%). Per irRC, in 21 pts, confirmed/not yet confirmed objective response rate (ORR) was 48%/57%; CR rate was 14%/24%. Median time to response was 17 wks."

Here is a report from a study using T-VEC alone:  "In a phase 2 trial reported in 2012, 20% of patients achieved a complete response and 28% gained an overall response.  92% of the responses were durable to at least 6 months, and the majority were ongoing with a range of 18-40 months.  Responses were found in patients with all stages and systemic tumors were eradicated in some patients."
Here is a link to posts that are:  All things T-VEC

Here T-VEC plus ipi was compared to ipi alone:

Primary results from a randomized (1:1), open-label phase II study of talimogene laherparepvec (T) and ipilimumab (I) vs I alone in unresected stage IIIB- IV melanoma.

ASCO 2017. J Clin Oncol 35, 2017. Chesney, Puzanov, Ross, et al.

Background: T is a HSV-1-based oncolytic virus designed to selectively replicate in tumors and produce GM-CSF to stimulate antitumor immune responses. I is an anti-CTLA-4 Ab [ipi/Yervoy] that blocks inhibition of activated T cells. This is the first randomized study to evaluate the addition of an oncolytic virus to a checkpoint inhibitor. Methods: The primary endpoint was ORR by immune-related response criteria. Key secondary endpoints: duration of response, disease control rate (DCR), PFS, OS, and safety. Prior treatment was allowed but not required. Pts had unresected stage IIIB-IV melanoma with measurable/injectable tumor(s) and no evidence of immunosuppression. T was given at approved dosing until no injectable tumors, disease progression (PD), or intolerance. I was started at w6 in T+I and at w1 in I at 3 mg/kg IV q3w x 4. Primary analysis occurred 6 m after last pt enrolled. Results: 198 pts were randomized: 98 T+I; 100 I. Characteristics were similar: 54% stage IIIB-IVM1a, 46% IVM1b/c. Median follow up time was 68 w (T+I) and 58 w (I). ORR was 38.8% (T+I) and 18.0% I, Odds ratio (OR) 2.9. 89% T+I and 83% I pts remain in response. Unconfirmed visceral lesion response was 35.5% T+I vs 13.6% I. OS is immature. Of 190 pts (safety set: 95 T+I, 95 I), most common adverse events (AEs) for T+I, I (%) were fatigue (59, 42), chills (53, 3), and diarrhea (42, 35). 28% T+I and 18% I pts had gr greater than/ = to 3 tx-related AE. There were 3 deaths (all unrelated) in T+I: 1 myocardial infarction and 2 PD. Conclusions: ORR was significantly higher for T+I vs I; responses were not limited to injected lesions. Toxicity of T+I combination was tolerable with no unexpected AEs. 

Here patients were Stage III/IV, some had had prior treatment, some not.  98 were given T-VEC and ipi, 100 got only ipi.  ORR to combo = 38.8%.  Ipi alone ORR = 18%.  

******************************************HF-10*******************************

Here is a study using HF-10, another HSV based intralesional, produced by Japanese company TaKaRa combined with ipi:

Final results of a phase II multicenter trial of HF10, a replication-competent HSV-1 oncolytic virus, and ipilimumab combination treatment in patients with stage IIIB-IV unresectable or metastatic melanoma.

ASCO 2017. J Clin Onco 35, 2017. Andtbacka, Ross, Agarwala, ...Grossmann.

Background: HF10 is a bioselected replication-competent oncolytic virus derived from HSV-1. Herein, we report the safety and efficacy data of HF10 + ipilimumab (ipi) combination treatment in a Phase II trial in melanoma. Methods: Key entry criteria: age greater than/= to 18 yrs, ECOG less than/= to 2, Stage IIIB, IIIC, or IV unresectable melanoma, ipi naïve (IV administration) and measurable non-visceral lesion(s) suitable for injection. HF10 injected into single or multiple tumors (1 x 10⁷ TCID₅₀/mL/dose, up to 5mL depending on tumor size and number); 4 injections q1wk; then up to 15 injections q3wk. Four ipi IV infusions (3 mg/kg; concurrent with HF10) were administered q3wk. AEs assessed per CTCAE 4.0. Tumor responses were assessed per mWHO and irRC at 12, 18, 24, 36 and 48 wks for patients (pts) continuing on HF10 monotherapy. Primary endpoint was Best Overall Response Rate (BORR) at 24 wks. Dose limiting toxicity (DLT) defined as greater than/= to G3 non-hematologic/hematologic toxicity, greater than/= G2 neurologic toxicity, or allergic event occurring within 1^st 3wks of therapy. Results: Of 46 pts enrolled and treated: 59% men, median age 67 yrs (range 28 to 91); disease stage 20% IIIB, 43% IIIC and 37% IV; 57% were treatment naïve and 43% with greater than/= to 1 prior cancer therapy for unresectable/metastatic melanoma. Most HF10-related AEs were less than/= to G2, similar to HF10 monotherapy. No DLTs were reported. 37% had greater than/= to G3 AEs, the majority due to ipi. HF10-related greater than/= to G3 AEs (n=3) were embolism, lymphedema, diarrhea, hypoglycemia, and groin pain. Of the 44 efficacy evaluable pts per irRC, BORR at 24 weeks was 41%; disease stability rate was 68%. As of Feb 06, 2017, median PFS was 19 months and median overall survival was 21.8 months. Conclusions: The combination HF10 and ipilimumab treatment demonstrated a favorable benefit/risk profile and encouraging antitumor activity in pts with stage IIIB, IIIC, or IV unresectable or metastatic melanoma. 

So...in this HF-10/ipi study - there were 46 patients, 63% of whom were Stage III and 37% Stage IV. About 1/2 were treatment naive and half had had at least one melanoma treatment.  Best ORR was 41%.  SD was attained in 68%.

********************************SD-101****************************

Here, SD-101, a different type of intralesional entirely, a TLR9 agonist from Dynavax, is paired with Pembro:

Phase 1b/2, open label, multicenter, study of intratumoral SD-101 in combination with pembrolizumab in anti-PD1 naïve and experienced metastatic melanoma patients.

ASCO 2017. J Clin Onco 35, 2017. Leung, Kummar, Agarwala, etal.

Background: SD-101 is a synthetic CpG-ODN agonist of TLR 9 that stimulates dendritic cells to release IFN-alpha and mature into antigen presenting cells to activate T cell anti-tumor responses. Pembro is a PD-1 inhibitor approved for the treatment of metastatic melanoma. This study, MEL-01 assesses the safety and preliminary efficacy of SD-101 in combination with pembro in stage IIIC-IV melanoma. Methods: A modified 3+3 design was used for SD-101 dose escalation of 1, 2, 4, and 8 mg injected in a single tumor lesion Q1W x 4 then Q3W x 7 in combination with pembro (200 mg IV Q3W). Tumor responses were assessed per investigator using RECIST v1.1. Results: In phase Ib, 22 pts were enrolled: median age 64 y/o, male 68%, white 82%, Stage IV/IIIc 86%/14%, LDH greater than 1 ULN 27%, greater than/= to 3 prior lines therapy 36%, anti-PD-1 naïve (n = 9) and experienced (n = 13). There has been no dose limiting toxicity (DLT) to date. The most common (greater than/= to 20%) treatment-related AEs (TRAEs) were transient low-grade fatigue, myalgia, headache, chills and injection site reactions. Grade greater than/ = to3 TRAEs were observed in 59.1% pts (most common: myalgia 13.6% and injection site pain 13.6%). Immune-related AEs occurred in 2 pts. One had a G2 pneumonitis on Day 23 resulting in drug withdrawal and the other G3 hypophysitis (85 days after last treatment). No deaths occurred. Responses were observed at all doses in PD-1 inhibitor naïve pts, both at the injected and non-injected lesions. A response was seen at the 8 mg dose in PD-1 inhibitor experienced pts. With median f/u of 97 days (max 382), the ORR was 66.7% in the PD-1 inhibitor naïve patients with best overall response of CR 22.2% (n = 2), PR 44.4% (n = 4), SD 11.1% (n = 1), PD 11.1% (n = 1), and NE 11.1% (n = 1). In the PD-1 inhibitor experienced pts: PR 7.7% (n = 1) and SD 38.5% (n = 5). Conclusions: The combination of SD-101 and pembro was well tolerated and demonstrates no worsening of the expected toxicities of each of the individual monotherapies. These interim data support enhanced activity of adding SD-101 to pembro in anti-PD-1 naive metastatic melanoma as well as potential activity in anti-PD-1 experienced pts. 

Patients were Stage III/IV (14 and 86% respectively).  Of the 22, 9 were anti-PD-1 naive and 13 had already taken it.  SD-101 was injected into a single lesion and patients were also given pembro.  No matter the SD-101 dose, patients who had never had anti-PD1 before, all had a response in injected and non-injected lesions for an ORR of 66.7%, CR of 22%, PR of 44%, SD of 11%.  In patients who had had anti-PD-1 previously, there was a partial response in almost 8% and stable disease in 38%.
This is a very small sample.  

**************************SUMMARY*************************
Okay.  Why in the world we cannot have studies constructed in ways that make sense is beyond me!!! We KNOW the results of ipi alone...a 15-18% response rate is typical and that was borne out here. Why we cannot have a very simple study directly comparing T-VEC to CAVATAK to PV-10 and whatever other intralesionals there are on the market is nutters!  I have been calling for it for years....but clearly no one listens to me!  However, it seems that no matter the intralesional presented here....they all can kill the melanoma tumor they are injected into and other lesions hanging about the body elsewhere.  When used alone, CAVATAK and T-VEC studies report about a 28% ORR, while PV-10 has studies reporting a 50% ORR.  I don't have data on HF-10 and SD-101 when used alone. When used with ipi, HF-10, T-VEC, and CAVATAK boosted ipi's usual response rate of about 15% to about 40%. When SD-101 was paired with pembro (anti-PD-1), pembro's usual response rate of about 40% was boosted to 66%.  Why we are pairing these drugs with ipi is another huge question for me! Let's see....ipi has lower response rates and higher side effect risks than anti-PD-1....but I digress. As we have already learned in many other studies...treatment naive patients did better...but even those who had already been through the wringer did have a chance of a response. I still feel that intralesionals, whose side effects are pretty much limited to local redness and irritation at the injection site with some fever and fatigue, have a lot of promise and their effectiveness in getting rid of lesions that were NOT EVEN INJECTED should be able to teach us a great deal about how melanoma works and hides.  Pairing intralesionals with anti-PD-1 as well as radiation appears to be a treatment methodology that could clearly benefit many.

Hang in there ratties....and...thanks.  - c

Reviews of T-VEC in melanoma patients: alone, with ipi or with pembrolizumab ~

I have been a fan of intraleional (also referred to as intratumoral) treatment - therapies that are injected directly into melanoma lesions - for a long time.  Here are a bazillion reports: Intralesional therapies for melanoma

While T-VEC is currently the only version with FDA approval, here is a list of some of the drugs most often used:
CAVATAK - derived from the Coxsackievirus
T-VEC - also called OncoVEX, Imlygic,  or Talimogene Laherparepvec - uses the herpes virus with GM-CSF
PV-10 - derived from Rose Bengal
HF10 - also derived from HSV
SD101 - a TLR9 agonist
IL-2 -  is also being used

Now this -

Patterns of response with talimogene laherparepvec in combination with ipilimumab or ipilimumab alone in metastatic unresectable melanoma.  Chesney, Puzanov, Collichio, et al. Br J Cancer. 2019 Jul 29. 

Talimogene laherparepvec (T-VEC) has demonstrated efficacy for unresectable melanoma. We explored response patterns from a phase 2 study evaluating patients with unresectable stage IIIB-IVM1c malignant melanoma who received T-VEC plus ipilimumab or ipilimumab alone. Patients with objective response per modified irRC were evaluated for pseudo-progression (single greater than/= to 25% increase in tumour burden before response). Patients without pseudo-progression were classified by whether they responded within or after 6 months of treatment start; those with pseudo-progression were classified by whether pseudo-progression was due to increase in existing lesions or development of new lesions. Overall, 39% (n = 38/98) in the combination arm and 18% (n = 18/100) in the ipilimumab arm had an objective response. Eight responders (combination, n = 7; ipilimumab, n = 1) had pseudo-progression; most occurred by week 12 and were caused by an increase in existing lesions. These data reinforce use of T-VEC through initial progression when combined with checkpoint inhibitors.

We already have this report from 2017:  T-VEC plus ipi vs ipi alone ~ along with additional T-VEC data...  where it is noted that:  "...quite promising is the combination of talimogene laherparepvec and pembrolizumab. In the phase IB ­MASTERKEY-265 trial of 21 previously untreated patients, responses were seen in 57% of patients, including complete responses in 7 patients, with no dose-limiting toxicities.⁹ This regimen is now in phase III trials."...

Now, this -

Response to the Rechallenge With Talimogene Laherparepvec (T-VEC) After Ipilimumab/Nivolumab Treatment in Patient With Cutaneous Malignant Melanoma Who Initially Had a Progression on T-VEC With Pembrolizumab.  Afzal, Shirai.  J Immunother. 2019 Mar 29.   Talimogene laherparepvec (T-VEC) is approved for unresected stage III-IV malignant melanoma. T-VEC has a direct cytotoxic effect and enhances the antitumor immunity of host cells. Immune checkpoints inhibitors also enhance the immunity of host cells by increasing the recruitment of antigen-presenting cells or activation and restoration of T-cell functions. Both type of therapies can potentiate the effect of the other therapy. We are reporting a case of T-VEC rechallenge who initially progressed on T-VEC with pembrolizumab but then responded to T-VEC rechallenge after intervening ipilimumab/nivolumab. An 83-year-old man developed a subungual lesion of the left thumb and found to have AJCC V. 7 stage IIIb melanoma. Few months later, he developed axillary lymphadenopathy and multiple subcutaneous nodules (AJCC V. 7 stage IIIc). The patient was started on intralesional rose Bengal and pembrolizumab. After 4 cycles of pembrolizumab with rose Bengal, a positron-emission tomography/computerized tomography scan showed the progression of disease. He was started on T-VEC intralesional injections with concurrent pembrolizumab, however, after 3 T-VEC injections and 2 more cycles of pembrolizumab, there was the progression of disease. Subsequently, ipilimumab/nivolumab was started and patient responded partially. Ipilimumab/nivolumab was held due to toxicity. Eight weeks from the last dose of ipilimumab/nivolumab, he experienced locoregional progression and was rechallenged with T-VEC monotherapy. The patient showed a significant response after second T-VEC injection and continued to show response 6 months since rechallenge. After, initial progression on T-VEC with pembrolizumab, intervening immune checkpoints inhibitors may favorably modify the antitumor immunity and potentiate antitumor effect of T-VEC rechallenge.

Cases like this are so difficult to understand - by the patient - poor soul, mostly - but also:  Did the rechallenge with T-VEC really turn the tide?  Or - did all the other therapies - or ONE of the other therapies - finally kick in and just needed more time to work?  We really can't say.  Patients who have experienced multiple therapies and then finally respond, hold the key to many questions.  I'm just not sure we know what exactly they unlock.

Then, this -

Final analyses of OPTiM: a randomized phase III trial of talimogene laherparepvec versus granulocyte-macrophage colony-stimulating factor in unresectable stage III-IV melanoma.  Andtbacka Collichio, Harrington, et al.  J Immunother Cancer. 2019 Jun 6.

Talimogene laherparepvec is an oncolytic immunotherapy approved in the US, Europe, Australia and Switzerland. We report the final planned analysis of OPTiM, a randomized open-label phase III trial in patients with unresectable stage IIIB-IVM1c melanoma.

Patients were randomized 2:1 to receive intratumoral talimogene laherparepvec or subcutaneous recombinant GM-CSF. In addition to overall survival (OS), durable response rate (DRR), objective response rate (ORR), complete responses (CR), and safety are also reported. All final analyses are considered to be descriptive and treatment responses were assessed by the investigators.

Of 436 patients in the intent-to-treat population, 295 were allocated to talimogene laherparepvec and 141 to GM-CSF. Median follow-up in the final OS analysis was 49 months. Median OS was 23.3 months (19.5-29.6) and 18.9 months (16.0-23.7) in the talimogene laherparepvec and GM-CSF arms, respectively . DRR was 19.0 and 1.4%; ORR was 31.5 and 6.4%. Fifty (16.9%) and 1 (0.7%) patient in the talimogene laherparepvec and GM-CSF arms, respectively, achieved CR. In talimogene laherparepvec-treated patients, median time to CR was 8.6 months; median CR duration was not reached. Among patients with a CR, 88.5% were estimated to survive at a 5-year landmark analysis. Talimogene laherparepvec efficacy was more pronounced in stage IIIB-IVM1a melanoma as already described in the primary analysis. The safety reporting was consistent with the primary OPTiM analysis.

In this final planned OPTiM analysis, talimogene laherparepvec continued to result in improved longer-term efficacy versus GM-CSF and remained well tolerated. The final analysis also confirms that talimogene laherparepvec was associated with durable CRs that were associated with prolonged survival.

This is one of those studies that gets on my nerve.  We wouldn't have expected GM-CSF to do much better than it did!!!!  But, I guess it shows what T-VEC can do on its own.

And finally, this:

Intratumoral Immunotherapy-Update. Hamid, Ismail, Puzanov.  Oncologist.  2019 Nov 29.

Intratumoral immunotherapies aim to trigger local and systemic immunologic responses via direct injection of immunostimulatory agents with the goal of tumor cell lysis, followed by release of tumor-derived antigens and subsequent activation of tumor-specific effector T cells. In 2019, a multitude of intratumoral immunotherapies with varied mechanisms of action, including nononcolytic viral therapies such as PV-10 and toll-like receptor 9 agonists and oncolytic viral therapies such as CAVATAK, Pexa-Vec, and HF10, have been extensively evaluated in clinical trials and demonstrated promising antitumor activity with tolerable toxicities in melanoma and other solid tumor types. Talimogene laherparepvec (T-VEC), a genetically modified herpes simplex virus type 1-based oncolytic immunotherapy, is the first oncolytic virus approved by the U.S. Food and Drug Administration for the treatment of unresectable melanoma recurrent after initial surgery. In patients with unresectable metastatic melanoma, T-VEC demonstrated a superior durable response rate (continuous complete response or partial response lasting greater than/= to6 months) over subcutaneous GM-CSF (16.3% vs. 2.1%). Responses were seen in both injected and uninjected lesions including visceral lesions, suggesting a systemic antitumor response. When combined with immune checkpoint inhibitors, T-VEC significantly improved response rates compared with single agent; similar results were seen with combinations of checkpoint inhibitors and other intratumoral therapies such as CAVATAK, HF10, and TLR9 agonists. In this review, we highlight recent results from clinical trials of key intratumoral immunotherapies that are being evaluated in the clinic, with a focus on T-VEC in the treatment of advanced melanoma as a model for future solid tumor indications.

IMPLICATIONS FOR PRACTICE: This review provides oncologists with the latest information on the development of key intratumoral immunotherapies, particularly oncolytic viruses. Currently, T-VEC is the only U.S. Food and Drug Administration (FDA)-approved oncolytic immunotherapy. This article highlights the efficacy and safety data from clinical trials of T-VEC both as monotherapy and in combination with immune checkpoint inhibitors. This review summarizes current knowledge on intratumoral therapies, a novel modality with increased utility in cancer treatment, and T-VEC, the only U.S. FDA-approved oncolytic viral therapy, for medical oncologists. This review evaluates approaches to incorporate T-VEC into daily practice to offer the possibility of response in selected melanoma patients with manageable adverse events as compared with other available immunotherapies.

For those interested, here's a direct link to the abstract above:  Intratumoral Immunotherapy-Update 2019.

So - there you have it. NOW!!!  We need direct head-to-head comparisons of some of these other intralesionals (PV-10, CAVATAK, etc.) to T-VEC.  I also think it is clear that generally, intralesional therapy COMBINED with anti-PD-1 is the way to go - whether you are Stage III or IV.   But, that's just me...

Thanks, ratties.  You change the world! - c

Study on Intralesional Rose Bengal out of Moffitt...we know a bit more about HOW it works!!!

In 2013 I wrote this:  "I first wrote about PV-10 (also known as Rose Bengal, a pretty cheap derivative of fluorescein, that has been used for over 80 years to stain necrotic tissue in the cornea when corneal abrasions are suspected and as an IV diagnostic of liver impairment) being used in melanoma patients in October of 2012.  The study I reported on was one in which Stage 3-4 melanoma patients had up to 4 courses of PV-10 injections into up to 20 cutaneous and subcutaneous tumors.  The cool thing was that not only did many of the injected tumors respond and shrivel, but some tumors at distant sites (even in the lungs) that were NOT injected, shriveled as well!!!"

And this in 2014:  "Intralesional melanoma therapy (A procedure in which the "treatment" is directly injected into superficial tumors and in theory, not only does that tumor die, but "by stander" tumors at more distant sites die too!!!) was first recorded back in 1975.  A 75 year old male with 64 melanoma mets just below the skin, as well as junk in his lungs, had 17 superficial lesions injected with Bacille Calmette-Guerin over a period of 8 months. (BCG is a vaccine against some strains of tuberculosis, but does contain a weakened version of the bacteria itself within it.) In the end, all 17 tumors injected resolved and his pulmonary mets diminished by more than 50%!  However, enthusiasm for BCG as a melanoma treatment waned as patients in subsequent trials experienced anaphylactic reactions and death due to disseminated BCG, and randomized trials failed to replicate significant clinical benefit.

Later, intralesional therapy was tried using all sorts of things.  More recently Allovectin-7, OncoVEX, and PV-10 have demonstrated positive results, killing melanoma at the injected site and systemically.  [Now we also have CAVATAK, an intralesional derived from the Coxsackievirus:  CAVATAK: intralesional therapy derived from the Coxsackievirus]

Allovectin-7, is a soup of DNA, that attempts to change the gene make-up of tumor cells. In a study reported in 2012, it provided a 12% overall response rate with no grade 3 or higher toxicities in patients with stage III/IV melanoma with injectable cutaneous lesions.

OncoVEX is a 2nd generation herpes virus embedded with GM-CSF...a substance that causes the body to make more white cells. (GM-CSF can be given to premature babies and leukemia patients with low white cell counts to help build them back up....and reverse immune suppression.) But, in OncoVEX, it is thought to only replicate in the tumor cells.  The white cells produced in the process kill off the tumor cells.  In a phase 2 trial reported in 2012, 20% of patients achieved a complete response and 28% gained an overall response.  92% of the responses were durable to at least 6 months, and the majority were ongoing with a range of 18-40 months.  Responses were found in patients with all stages and systemic tumors were eradicated in some patients.

Rose Bengal was first utilized in the 1800's to dye fabrics and color the feet of Bengali women red for weddings and celebrations. Later it was used as a staining agent to find corneal lesions and then as an IV preparation to check for impaired liver function.  The "Aha!" moment came in the 1980's when Japanese tests of a "food dye" to determine tumor origin, found dose-dependent survival increases. After a few other sundry studies....PV-10 was born.  It is a 10% Rose Bengal solution, with a 30-minute half-life, excreted via bile. PV-10 is excluded from normal cells, but slips through the cell membrane of cancer cells (liver, breast, melanoma, and others) because their cell walls have a higher lipid content. Once inside, PV-10 triggers lysosomal release (the part of the cell that digests waste), killing the cell in 30-60 minutes. Antigenic tumor fragments are believed to produce the 'bystander effect' leading to immediate reduction in tumor burden and concomitant immunologic activation."

Here is a link to the entire report and others I've posted here:  Info from ASCO 2014 on Rose Bengal (PV-10) and links to more reports

And now....researchers have learned a little more about how it actually works....

Intralesional rose bengal in melanoma elicits tumor immunity via activation of dendritic cells by the release of high mobility group box 1.  Liu, Innamarato, Kodumudi, Weber, et al.  Oncotarget. 2016 May 9.

"Intralesional (IL) therapy is under investigation to treat dermal and subcutaneous metastatic cancer. Rose Bengal (RB) is a staining agent that was originally used by ophthalmologists and in liver function studies. IL injection of RB has been shown to induce regression of injected and uninjected tumors in murine models and clinical trials. In this study, we have shown a mechanism of tumor-specific immune response induced by IL RB. In melanoma-bearing mice, IL RB induced regression of injected tumor and inhibited the growth of bystander lesions mediated by CD8+ T cells. IL RB resulted in necrosis of tumor cells and the release of High Mobility Group Box 1 (HMGB1), with increased dendritic cell (DC) infiltration into draining lymph nodes and the activation of tumor-specific T cells. Treatment of DC with tumor supernatants increased the ability of DCs to stimulate T cell proliferation, and blockade of HMGB1 in the supernatants suppressed DC activity. Additionally, increased HMGB1 levels were measured in the sera of melanoma patients treated with IL RB. These results support the role of IL RB to activate dendritic cells at the site of tumor necrosis for the induction of a systemic anti-tumor immune response."

Bentie has always believed that dendritic cells are going to hold some important keys to understanding and perhaps treating melanoma!  Way to go ratties (and little melanoma-bearing mice)! - c

Intratumoral (intralesional) therapy and a new guy in town: IL-12 Plasmid Transfection (tavo) with pembro

I've been a fan of incorporating intratumoral/intralesional therapy into melanoma care for some time.  Here's proof:  A zillion articles on intralesional therapy

Now this ~

Intratumoral Immunotherapy-Update 2019.  Hamid, Ismail, Puaznov.  Oncologist.  2020 Mar;25.

Intratumoral immunotherapies aim to trigger local and systemic immunologic responses via direct injection of immunostimulatory agents with the goal of tumor cell lysis, followed by release of tumor-derived antigens and subsequent activation of tumor-specific effector T cells. In 2019, a multitude of intratumoral immunotherapies with varied mechanisms of action, including nononcolytic viral therapies such as PV-10 and toll-like receptor 9 agonists and oncolytic viral therapies such as CAVATAK, Pexa-Vec, and HF10, have been extensively evaluated in clinical trials and demonstrated promising antitumor activity with tolerable toxicities in melanoma and other solid tumor types. Talimogene laherparepvec (T-VEC), a genetically modified herpes simplex virus type 1-based oncolytic immunotherapy, is the first oncolytic virus approved by the U.S. Food and Drug Administration for the treatment of unresectable melanoma recurrent after initial surgery. In patients with unresectable metastatic melanoma, T-VEC demonstrated a superior durable response rate (continuous complete response or partial response lasting ≥6 months) over subcutaneous GM-CSF (16.3% vs. 2.1%). Responses were seen in both injected and uninjected lesions including visceral lesions, suggesting a systemic antitumor response. When combined with immune checkpoint inhibitors, T-VEC significantly improved response rates compared with single agent; similar results were seen with combinations of checkpoint inhibitors and other intratumoral therapies such as CAVATAK, HF10, and TLR9 agonists. In this review, we highlight recent results from clinical trials of key intratumoral immunotherapies that are being evaluated in the clinic, with a focus on T-VEC in the treatment of advanced melanoma as a model for future solid tumor indications.  This review provides oncologists with the latest information on the development of key intratumoral immunotherapies, particularly oncolytic viruses. Currently, T-VEC is the only U.S. Food and Drug Administration (FDA)-approved oncolytic immunotherapy. This article highlights the efficacy and safety data from clinical trials of T-VEC both as monotherapy and in combination with immune checkpoint inhibitors. This review summarizes current knowledge on intratumoral therapies, a novel modality with increased utility in cancer treatment, and T-VEC, the only U.S. FDA-approved oncolytic viral therapy, for medical oncologists. This review evaluates approaches to incorporate T-VEC into daily practice to offer the possibility of response in selected melanoma patients with manageable adverse events as compared with other available immunotherapies.

And this ~

Phase II Trial of IL-12 Plasmid Transfection and PD-1 Blockade in Immunologically Quiescent Melanoma.  Algazi, Twitty, Tsai, et al.  Clin Cancer Res.  2020 May 6.

Tumors with low frequencies of checkpoint positive tumor-infiltrating lymphocytes (cpTIL) have a low likelihood of response to PD-1 blockade. We conducted a prospective multicenter phase II trial of intratumoral plasmid IL-12 (tavokinogene telseplasmid; "tavo") electroporation combined with pembrolizumab in patients with advanced melanoma with low frequencies of checkpoint positive cytotoxic lymphocytes (cpCTL).

Tavo was administered intratumorally days 1, 5, and 8 every 6 weeks while pembrolizumab (200 mg, i.v.) was administered every 3 weeks. The primary endpoint was objective response rate (ORR) by RECIST, secondary endpoints included duration of response, overall survival and progression-free survival. Toxicity was evaluated by the CTCAE v4. Extensive correlative analysis was done.

The combination of tavo and pembrolizumab was well tolerated with adverse events similar to those previously reported with pembrolizumab alone. Patients had a 41% ORR (n = 22, RECIST 1.1) with 36% complete responses. Correlative analysis showed that the combination enhanced immune infiltration and sustained the IL-12/IFNγ feed-forward cycle, driving intratumoral cross-presenting dendritic cell subsets with increased TILs, emerging T cell receptor clones and, ultimately, systemic cellular immune responses.

The combination of tavo and pembrolizumab was associated with a higher than expected response rate in this poorly immunogenic population. No new or unexpected toxicities were observed. Correlative analysis showed T cell infiltration with enhanced immunity paralleling the clinical activity in low cpCTL tumors.

And finally, this ~

Insights Into the Molecular Mechanisms Behind Intralesional Immunotherapies for Advanced Melanoma.  Vidovic and Giacomantonio.  Cancers (Basel) 2020 May 22. 

 The incidence of cutaneous melanoma, a highly malignant skin cancer, is increasing yearly. While surgical removal of the tumor is the mainstay of treatment for patients with locally confined disease, those with metastases face uncertainty when it comes to their treatment. As melanoma is a relatively immunogenic cancer, current guidelines suggest using immunotherapies that can rewire the host immune response to target melanoma tumor cells. Intralesional therapy, where immunomodulatory agents are injected directly into the tumor, are an emerging aspect of treatment for in-transit melanoma because of their ability to mitigate severe off-target immune-related adverse events. However, their immunomodulatory mechanisms are poorly understood. In this review, we will summarize and discuss the different intralesional therapies for metastatic melanoma with respect to their clinical outcomes and immune molecular mechanisms.

For what it's worth.  Hang tough, ratties!!! - c