Dr. Vanita Noronha from the Tata Memorial Centre in Mumbai emphasizes the need for rethinking drug dosing approaches for modern therapies like nivolumab, an immunotherapy. Ongoing and planned trials in India are exploring cost-effective alternative dosing regimens due to the prohibitive cost of standard-dose therapies.
Dr. Vanita Noronha from the Tata Memorial Centre highlighted the role of factors such as pharmacokinetics, pharmacodynamics, receptor affinity, and drug elimination in determining drug dosing during a Q&A session with Clinical Advances in Hematology & Oncology. The traditional dosing approach does not apply to modern therapies like nivolumab, an immunotherapy that binds to the PD-1 protein. According to Dr. Noronha, the drug reaches receptor saturation at a low dose, and hence increasing dosage does not increase receptor binding. For nivolumab to be effective, 70-75% of the PD-1 receptor needs to be occupied, which occurs at a dose of 0.3 mg/kg, only a tenth of the usually administered dose of 3 mg/kg.
Dr. Noronha further described a study published in the Journal of Clinical Oncology in 2023 on low-dose nivolumab in head and neck cancer. The study, conducted with Indian patients who cannot afford standard dosing, used a regimen of oral metronomic chemotherapy along with low-dose nivolumab. This trial significantly improved 1-year overall survival (OS) and other efficacy parameters without substantial increase in toxicity. She also emphasized ongoing and planned trials examining alternative dosing regimens of immunotherapy and other drugs due to the cost-prohibitive nature of standard-dose therapies in regions like India.