Itching and vitiligo associated with progression free survival after Pembro/Keytruda???!

Pembrolizumab cutaneous adverse events and their association with disease progression.  Sanlorenzo, Vujic, Daud, Algazi, et al.  JAMA Dermatol.  2015 Jul 29.

While immunomodulatory anticancer drugs, like anti-PD1 are promising....little is known about cutaneous adverse events caused..and their possible correlation with treatment response.  Single institution, retrospective medical record review, March 1, 2011 - May 28, 2014.  83 patients from 2 clinical trials...who had at least 1 dose of pembro and at least 1 f/u visit.  43 patients had 10mg/kg q 3 wks, 24 had 10mg/kg q 2 wks, and 16 had 2mg/kg q 3 weeks.  66 were melanoma pts, 15 were lung, 1 prostate cancer and another was treated for Merkel cell carcinoma.  

35 patients (42%) developed cutaneous AE's.  Most common = papular eruption (24[29%]), itching (10[12%]), hypopigmentation {vitiligo} (7[8%]).  All 7 pts who developed hypopigmentation were being treated for melanoma.  Survival analyses showed that patients who developed cutaneous AE's had significantly longer progression-free intervals in all 3 treatment dosage groups, compared to patients who did not develop cutaneous AE's.

CONCLUSION:  Pembro was associated with side effects related to the skin in 42% of patients.  The development of these cutaneous AE's, especially hypopigmentation in patients with melanoma, could point toward better treatment response.


Link to post describing general side effects from anti-PD-1 and why we get them:  Side effects of anti-PD1 (Nivo in this case, though data is very similar for Pembro)

Link to post from ASCO 2015:  How Nivo side effects are associated with survival

Link with info from 2015 with article demonstrating positive link between vitiligo and remission of melanoma, back ground info, and white patches:  Vitiligo a good prognostic indicator for melanoma

Pretty much what we've been hearing (and seeing!!) already.  There has got to be something going on between the CD8 T cells, dendritic cells and melanoma, especially since only the melanoma patients in the study developed vitiligo.  B's been screaming about this for years!!!  It is clear that a link between these things exists...but we don't yet know how to ELICIT the vitiligo response so that more melanoma patients GET a response!  Come on researchers!!!  We've got a vaccine for ebola, a reliable treatment for Hep C...let's do this!!!!! - c