Panobinostat Regimen Yields Benefit for R/R Myeloma After Frontline ASCT

Panobinostat (Farydak) in combination with gemcitabine (Gemzar), busulfan (Busulfex), and melphalan (Megace Alkeran) produced positive evidence of clinical activity in patients with relapsed or refractory multiple myeloma, especially after first autologous stem cell transplant (ASCT), according to Yago L. Nieto, MD, PhD.

In an interview with CancerNetwork^®, Nieto, a professor in the Department of Stem Cell Transplantation and Division of Internal Medicine at the University of Texas MD Anderson Cancer Center, described the design of a matched pair comparison with a concurrent control cohort (NCT02506959) assessing the regimen and detailing efficacy.

In a population of 80 patients who received the regimen, the median progression-free survival was 45 months, 21 months, and 32 months after frontline ASCT-1, first salvage ASCT-1, and second ASCT, respectively; the median follow-up was 51 months.

Lead author, Nieto, presented these findings as part of an abstract at the 2023 Tandem Meeting.

Transcript:

It was not a randomized trial but it's good evidence because a matched pair concurrent control analysis is likely the second-best evidence we have next to randomized trials. This [was a] rationally designed regimen of panobinostat, gemcitabine, busulfan, and melphalan.

I say ‘rationally’ because it was designed based on our work in the lab where we saw that there was striking synergism between panobinostat, which is the best HDAC inhibitor we have, and gemcitabine, busulfan and melphalan, with a great increase of cytotoxicity, apoptosis, and markers of DNA damage on the myeloma cells.

We saw that there's improvement of progression-free survival, which is a perfectly valid end point given that overall survival requires much longer follow-up. It's also contingent on the therapies you have available upon relapse, [which] keep getting better. It's going to be very difficult to encounter overall survival differences in myeloma in any study.

We saw that there's an improvement of progression-free survival compared with our matched controls when first transplant is done, either for patients with high-risk disease or relapsed disease. In the future, it may be the only kind of transplant we're going to be doing for myeloma; second transplants may not play much of a role given the availability of CAR T and other therapies.

Reference

Nieto Y, Yang Z, Valdez BC, et al. Safety and efficacy of a new high-dose chemotherapy regimen of panobinostat, gemcitabine, busulfan and melphalan (Pano/GBM) with autologous stem cell transplant (ASCT) for patients with high-risk or refractory/relapsed myeloma – matched pair comparisons with a concurrent control cohort. Transplantation and Cellular Therapy. 2023;29(suppl 2):S31-S32.