Evaluating Combination of Nivolumab and Axatilimab in Patients With Relapsed/Refractory Classical Hodgkin Lymphoma

This study is a phase II, proof-of concept, prospective, multi-center study of combination of nivolumab and Axatilimab (SNDX-6352) in subjects with relapsed/refractory classical Hodgkin lymphoma. Nine evaluable patients will be enrolled and receive Axatilimab 3mg/kg Q4 weeks in combination with nivolumab 480mg Q4 weeks. If more than one DLT is observed during the DLT period (first two cycles) in the first 6 patients, the study drug dose will be reduced to 2mg/kg and additional patients (up to 6 at 2mg/kg dose) may be included to the study. This could result in maximum 12 patients for the entire study. The combination of Nivolumab and Axatilimab will be continued until progression/toxicity or a maximum of 12 months of treatment. The investigators expect that in patients who respond to this combination, the tumor microenvironment will shift towards immunocompetent phenotype within a few months of combination treatment. Thus, there may not be further benefit of continuing the combination for more than 12 months. If patients have responded to the combination, patients are able to continue anti-PD(L)1 off-study after 12 months as their tumor microenvironment might have reset for it to work better. Safety Run-In A total of 6 to 9 subjects may be evaluated in Part 1 depending on the frequency of DLTs and the need for dose reductions. A dose de-escalation design will be used to determine the recommended phase 2 dose, while ensuring the safety and tolerability of the treatment. In this trial, the dose determined to be the maximum tolerated dose will be the recommended phase 2 dose for a potential future study. The study may test two dose levels of Axatilimab (SNDX-6352) as described in the protocol.