At last year’s American Society of Hematology (ASH) annual meeting, Amgen drew attention for a 70% response rate achieved in an early clinical trial of its anti-BCMA T-cell engager for multiple myeloma, though the company was dogged by questions about whether the time-consuming infusions the treatment requires could compete with up-and-coming CAR-T cell therapies. At the time, Amgen was advancing a follow-up drug that has a longer half-life than its predecessor—and therefore could be less burdensome to patients.
At this year’s ASH meeting, Dana-Farber Cancer Institute researchers presented a preclinical study they believe shows the promise of the follow-up drug, AMG 701, for treating multiple myeloma and for preventing relapses of the disease.
The Dana-Farber team administered three injections of AMG 701 into mice with myeloma tumors and observed that their cancers disappeared.
When they combined AMG 701 with Revlimid, the immunomodulatory drug that’s been a blockbuster for Bristol-Myers Squibb’s newly acquired Celgene, the results were even better. The combination suppressed tumor growth over the long term, preventing relapse, they said. Mice that received only the BiTE treatment or Revlimid, by contrast, eventually relapsed.
Bispecific T-cell engagers, or BiTEs, have two sections. One attaches to a protein on a cancer cell, while the other binds to a cancer-killing T cell, activating it to attack tumors. Unlike CAR-T treatments, which are made from individual patients’ cells, BiTEs are off the shelf, so they can be prescribed and administered with no delay. The technology has already produced one winner for Amgen—Blinctyo to treat acute lymphoblastic leukemia. Sales of that drug jumped 47% in the third quarter of this year.
But in multiple myeloma, Amgen could be facing a much more challenging competitive picture, particularly from CAR-T treatments, which continue to steal the spotlight. Over the weekend at ASH, for example, Johnson & Johnson said that in a phase 1 trial, its BCMA-targeted CAR-T treatment eliminated tumors in 69% of patients with advanced multiple myeloma. That treatment is slated to move into a phase 2 trial that could read out by the end of next year.
And there are other companies developing bispecific antibodies, too. In February, AbbVie formed a $90 million development pact with Teneobio affiliate TeneoOne to develop a bispecific for multiple myeloma that targets BCMA and CD3.
Amgen is testing its original BiTE for multiple myeloma, called AMG 420, in a phase 1b/2 study.
Meanwhile, Amgen has launched a phase 1 study of AMG 701 in multiple myeloma, which will enroll 150 patients and is slated to be completed in 2021. The Dana-Farber researchers who presented the preclinical study at ASH believe the results justify extensive human test of the drug—both as a monotherapy and in combination with treatments like Revlimid, “to enhance elimination of residual diseases and prolong long-term durable responses,” they said in a statement.