Efficacy of low-dose nivolumab in advanced cancers: A retrospective analysis from medical oncology clinic in Eastern India.

Abstract

2598 Background: Immunotherapy with PD-1/PDL1 blocking monoclonal antibodies has improved survival across several malignancies at different stages of these malignancies. But in Low- & middle-income countries, only 1-3% of cancer patients can access the standard dose of Immunotherapy. In this study, we aim to assess the response to low dose (LD) of Immunotherapy (nivolumab) across a broad range of malignancies. Methods: The study is a retrospective descriptive study. A total of 104 patients with advanced cancers were included in the study. Patients received a lower dose of Nivolumab (20/40 mg), ones in a 2-weekly-4weekly schedule, with treatment continued until disease progression or intolerable toxicity Their demographics, clinical profile, response to therapy, and adverse events were analyzed. Results: Male to female ratio was 5:1. The median age of patients was 49 years (range - 15 years to 78 years) and 70% patients were ECOG-PS 1-2 30% were ECOG-PS 3-4. Overall 56 patients were diagnosed with Squamous cell carcinoma (SCC) Head&neck, 15 had Renal cell carcinoma (RCC), 14 had Malignant melanoma, 5 had lung cancer, 4 with Hepatocellular carcinoma (HCC), 2 each of Gynecological cancer, Gall bladder cancer & CUP and 1 each of stomach cancer, Urinary bladder malignancy (HGUC), & Lymphoma. The most common metastatic sites were Lungs (46%) > Bone(27%) > Liver(15%). A total of 73 patients were included for assessment (received ≥2 cycles of Nivolumab). The overall response rate (ORR) was 39.7% and the Disease control rate (DCR) was 54.7%. Median PFS was 4 months (range - 1month to 26months) with Median OS being 11 months (range - 3months to 30months). Grade 3-4 adverse events were seen in 21/104(20%), the most common being dermatological (8/21) followed by anemia (7/21) and endocrinal AEs (4/21). Conclusions: Low-dose Nivolumab showed good response rates in advanced malignancies with manageable toxicities even in poor general condition. The cost of therapy was 1/5th to 1/10th of the standard dose of Nivolumab, highlighting its potential as a cost-effective alternative in resource-limited settings. Response and survival analysis. Charectiristics N=73 Response rates CR 5 PR 24 SD 11 PD 33 ORR 39.7% DCR 54.7% Survival analysis mPFS 4 months mOS 11.5 months