Bristol Myers drug delays myeloma progression in hard to treat patients

By Michael Erman

May 29 (Reuters) – Bristol Myers Squibb said on Friday that its experimental oral drug mezigdomide delayed disease progression in a late-stage trial of multiple myeloma patients whose illness had relapsed or not responded to other treatments.

The drugmaker said its SUCCESSOR-2 trial showed that mezigdomide added to a standard therapy of carfilzomib, sold as Kyprolis by Amgen, and the steroid dexamethasone reduced the risk of disease progression or death by 52%, compared to the standard treatment alone.

Median progression-free survival, or the time before the disease began to worsen, was 18 months for those who got the Bristol Myers drug versus 8.3 months for the control arm.

The results are being presented at the annual American Society of Clinical Oncology meeting in Chicago.

Mezigdomide belongs to a class of drugs called cereblon E3 ligase modulator (CELMoD) agents, as does iberdomide, another myeloma treatment Bristol Myers is developing. The U.S. FDA is expected to make an approval decision on iberdomide in August.

Bristol Myers Chief Medical Officer Cristian Massacesi said in an interview that the mezigdomide study involved patients at a very late stage of the blood cancer.

“The benefit we have seen… is remarkable considering the population that has been treated, so this speaks also on the potency of these drugs,” Massacesi said.

The overall response rate was 80.2% for patients on the mezigdomide regimen, while 53.4% responded to the standard therapy. Roughly triple the number of patients who received the Bristol Myers drug, or 27%, had a complete response, which usually means no detectable cancer.

Overall survival data is not yet available.

Side effects from the treatment were manageable, the company said, although 83.7% of mezigdomide patients had significant adverse events compared with 56.5% for the control group. The most common adverse event was neutropenia, abnormally low levels of a type of white blood cell.

Mezigdomide, as an oral medicine, could easily be used in community oncology clinics where most myeloma patients are treated, said Bristol Myers Chief Commercialization Officer Adam Lenkowsky.

“What we hear from physicians is they’re excited about oral regimens that are low burden and can provide a better overall experience for their patients,” Lenkowsky said.

The company sees the new drugs replacing older Bristol medicines Revlimid and Pomalyst, which are facing generic competition, in later lines of treatment, Lenkowsky said.

(Reporting by Michael Erman)