Abstract 1049P
Background
MM is a rare subtype of melanoma with distinct biology. Data on the efficacy of immunotherapy in MM is limited. We aimed to determine the immunotherapy efficacy by primary site (prim) and race.
Methods
Baseline characteristics of MM treated with PD1+/-IPI from 24 cancer centers were collected. Primary endpoints were response rate (RR), progression-free survival (PFS), overall survival (OS) by prim (naso-oral, urogenital, anorectal, other), race (Caucasian, Asian, Other) and treatment (PD1 v PD1+IPI). Univariate and multivariate Cox proportional hazard model analyses were conducted.
Results
518 pts were included; med age 64 yrs (range 25-93); 326 (63%) Caucasian, 154 (30%) Asian & 38 (7%) Other; 113 (22%) anorectal prim, 170 (33%) urogenital, 194 (38%) naso-oral & 41 (8%) other; 150 (29%) LDH >ULN at baseline; 328 (63%) received PD1 & 190 (37%) PD1+IPI; med f/u 34 months (17-50). Baseline characteristics were similar between PD1 v PD1+IPI, except Stage IV (79% v 70%, p=0.02). PD1+IPI was more frequent in Caucasians than Asians (40% v 14%, p<.001) RR did not differ by prim, race & treatment (Table). RR for naso-oral was numerically higher for PD1+IPI v PD1 for Caucasians (36% v 28%) & Asians (57% v 25%). Factors prognostic of short PFS were Stage IV (p=0.02), ≥2 organ metastases (mets) (p=0.01), ECOG PS ≥1 (p=0.01) & presence of liver (p=0.01), lung (p<0.01) & bone (p<0.01) mets. Factors prognostic of short OS were advanced Stage III/IV (p=0.04), ≥2 organ mets (p<0.01), ECOG PS ≥1 (p=0.01) & presence of liver (p=0.01), lung (p<0.01), bone (p<0.01) & pancreatic (p=0.01) mets. Table: 1049P
| Race | Treatment | Overall | ||||
| Caucasian | Asian | PD1 | PD1+IPI | |||
| Overall RR | 99/326 (30%) | 37/154 (24%) | 91/328 (28%) | 59/190 (31%) | 150/518 (29%) | |
| RR site | Anorectal | 26/80 (33%) | 5/24 (21%) | 20/68 (29%) | 16/45 (36%) | 36/113 (32%) |
| Urogenital | 33/121 (27%) | 8/37 (22%) | 31/99 (31%) | 15/71 (21%) | 46/170 (27%) | |
| Naso-oral | 36/123 (29%) | 19/66 (29%) | 35/130 (27%) | 24/64 (38%) | 59/194 (30%) | |
| RR race | PD1 | 57/189 (30%) | 29/128 (23%) | - | - | - |
| PD1+IPI | 42/137 (31%) | 8/26 (31%) | - | - | - | |
| PFS | mPFS mo (med, 95% CI) | 5 (4-6) | 4 (3-6) | 5 (4-6) | 4 (3-6) | 4 (4-6) |
| 3 yr PFS (95% CI) | 16% (12-21) | 17% (12-26) | 16% (13-22) | 16% (10-25) | 16% (13-21) | |
| OS | mOS mo (med, 95% CI) | 21 (18-26) | 18 (14-25) | 18 (16-23) | 21 (19-27) | 19 (18-24) |
| 3 yr OS (95% CI) | 33% (27-40) | 30% (22-42) | 32% (27-39) | 29% (21-40) | 32% (27-37) |
*Other site not shown
Conclusions
Pts with MM have poor prognosis. Efficacy of PD1+/-IPI is similar for site of prim & race. In Caucasians & Asians naso-oral was the most common prim site & showed numerically higher response to PD1+IPI. At other sites, addition of IPI does not appear to give greater benefit over PD1. Other clinical factors were predictive and prognostic for treatment outcome.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
K. Namikawa: Non-Financial Interests, Personal, Other: Ono pharmaceutical, Bristol-Myers Squibb, Novartis pharmaceutical, MSD, and Toray industries; Non-Financial Interests, Institutional, Research Grant: Ono pharmaceutical, Bristol-Myers Squibb, and Novartis pharmaceutical. E. Buchbinder: Non-Financial Interests, Personal, Advisory Role: Novartis, Apexigen, Shionogi and BMS; Non-Financial Interests, Institutional, Funding: Lilly, Novartis, Partners therapeutics, Genentech and BVD. L. Zimmer: Non-Financial Interests, Personal, Other: Roche, BMS, MSD, Novartis, Pierre Fabre; Non-Financial Interests, Personal, Advisory Board: BMS, Novartis, Pierre Fabre, Sunpharma, Sanofi, MSD; Non-Financial Interests, Institutional, Research Grant: Novartis; Non-Financial Interests, Personal, Other: BMS, Pierre Fabre, Sanofi, Amgen, Novartis, Sunpharma. M. Mooradian: Non-Financial Interests, Personal, Advisory Role: AstraZeneca, Immunai, Nektar Therapeutics, Catalyst Pharmaceuticals. D. Johnson: Non-Financial Interests, Personal, Advisory Board: Array BioPharma, Bristol Myers Squibb, Incyte, Merck and Novartis; Non-Financial Interests, Personal and Institutional, Research Grant: Bristol Myers Squibb and Incyte; Non-Financial Interests, Personal, Other: Genentech. J. GUO: Non-Financial Interests, Personal, Advisory Board: MSD, Roche, Pfizer, Bayer, Novartis, Simcere, Shanghai Junshi Bioscience, Oriengene. C. Lebbe: Non-Financial Interests, Personal, Other: Amgen, Bristol Myers Squibb, Incyte, Merck Sharp & Dohme, Novartis, Pfizer, Pierre Fabre and Roche; Non-Financial Interests, Personal, Advisory Board: Amgen, Bristol Myers Squibb, Merck Serono, Merck Sharp & Dohme, Novartis, Roche and Sanofi; Non-Financial Interests, Institutional, Research Grant: Bristol Myers Squibb and Roche; Non-Financial Interests, Personal, Other: Bristol Myers Squibb and Merck Sharp & Dohme. C. Robert: Non-Financial Interests, Personal, Advisory Role: BMS, Novartis, MSD, Roche, Pierre Fabre, Sanofi, Pfizer. M. Mandala: Non-Financial Interests, Personal, Advisory Board: BMS, MSD, and Pierre Fabre; Non-Financial Interests, Institutional, Funding: BMS, MSD, Roche Novartis. P. Bhave: Non-Financial Interests, Personal, Other: MSD; Non-Financial Interests, Personal, Other: Novartis. K.C. Kähler: Non-Financial Interests, Personal, Advisory Board: Roche, BMS, MSD; Non-Financial Interests, Personal, Other: Roche, BMS, MSD, GSK, Amgen. G.V. Long: Non-Financial Interests, Personal, Advisory Board: Aduro Biotech Inc, Amgen Inc, Array Biopharma inc, Boehringer Ingelheim International GmbH, Bristol-Myers Squibb, Hexel AG, Highlight Therapeutics S.L., Merck Sharpe & Dohme, Novartis Pharma AG, OncoSec, Pierre Fabre, QBiotics Group Limited, Regeneron Pha. All other authors have declared no conflicts of interest.