Bristol Myers Squibb has jettisoned another cancer candidate in-licensed under its former CEO. Immatics is the latest partner to get a termination notice, leaving it in full control of a bispecific molecule that BMS picked up for $150 million upfront late in 2021.
The deal, which featured $770 million in milestones, positioned BMS to collaborate with Immatics on the development of IMA401, a bispecific molecule that simultaneously targets MAGEA4/8 on solid tumors and activates T cells. BMS placed the bet before IMA401 entered the clinic—and has now cut its ties to the candidate just as Immatics shared the first phase 1 dose-escalation data.
Immatics said BMS ended the co-development deal because of its ongoing portfolio prioritization push, a statement that is supported by recent updates from the Big Pharma. Since Chris Boerner replaced Giovanni Caforio as CEO late last year, BMS has terminated a deal for Agenus’ TIGIT bispecific antibody, dropped a BCMA bispecific T-cell engager and returned an antibody-drug conjugate to Eisai.
BMS paid a combined $650 million upfront for the Agenus and Eisai candidates and only u-turned on its BCMA prospect after filing to run a phase 3 trial. Immatics shared details of BMS’ decision to walk away from another $150 million in upfront fees alongside an early look at clinical data on IMA401.
The presentation at the European Society for Medical Oncology (ESMO) Congress 2024 covers data on 35 people with 16 different solid tumors. Patients were both HLA-A*02:01 and MAGEA4/8-positive and had received a median of four prior lines of systemic treatments. Immatics studied IMA401 at nine escalating dose levels.
In the 29 people who were evaluable for efficacy, Immatics reported four confirmed objective responses. All four responses were in patients who received at least 1 mg of IMA401 and had high MAGEA4/8 levels. The response rate of 14% in the overall efficacy population rose to 25% in the subgroup defined by levels of IMA401 and MAGEA4/8.
Transient lymphopenia and mild to moderate cytokine release syndrome (CRS), typically after the first dose, were the most common treatment-related adverse events. In an earlier cut of the data included in the ESMO abstract, Immatics reported up to grade 4 lymphopenia but only grade 1 and 2 CRS. Grade 3/4 neutropenia, low levels of a white blood cell, didn’t reoccur after the introduction of dexamethasone.
Immatics, which was already responsible for the phase 1 trial, plans to advance IMA401 further through clinical development. Having switched from dosing every week to every two weeks after seeing clinical data, the biotech believes dosing every four weeks may be possible. Immatics said a four-week schedule would be ideal for potential combinations with checkpoint inhibitors. Updated data are due next year.