In September 2024, a readout from a separate trial of rocatinlimab elicited mixed reactions from analysts, who found the antibody’s efficacy in that study to be underwhelming.
Amgen’s anti-OX40 antibody rocatinlimab vindicated itself this weekend, with new Phase III data pointing to its strong efficacy in moderate to severe atopic dermatitis.
These findings come from the ROCKET-IGNITE study, one of eight trials under Amgen’s late-stage ROCKET clinical development program for rocatinlimab. Results showed that 42.3% of patients given 300-mg rocatinlimab once every four weeks saw at least a 75% reduction from baseline in Eczema Area and Severity Index scores (EASI-75) at 24 weeks. This treatment effect represented a significant 29.5% difference versus placebo, according to Amgen’s news release.
At this dose level, 23.6% of patients achieved clear or almost-clear skin at 24 weeks, representing a 14.9% advantage over placebo. Amgen presented these data Saturday at the 2024 annual meeting of the American Academy of Dermatology
Analysts at Leerink Partners called these findings “surprisingly positive” in an investor note on Sunday, pointing to a prior readout from ROCKET-HORIZON. Released in September 2024, data from the HORIZON trial found that 32.8% of rocatinlimab-treated patients achieved EASI-75, representing a 19.1% difference from placebo.
While Amgen at the time declared victory in HORIZON, calling rocatinlimab’s effect a “statistically significant improvement” in disease severity, analysts were unconvinced. Jefferies called the magnitude of effect “modest,” while BMO Capital Markets said the data “appear to fall short of agents like Ebglyss/Dupixent.” Leerink, in its note on Sunday, said it found HORIZON’s results to be “underwhelming.”
Meanwhile, IGNITE’s outcomes were “more compelling,” according to the Leerink analysts, despite testing a similar dose as HORIZON.
Still, the analysts flagged instances of pyrexia (fever) and chills—which they called an “adverse event of interest”—that occurred more frequently in rocatinlimab-treated patients. Amgen explained these side effects as “mainly a first dose effect and therefore not commonly seen on subsequent doses,” as per the Leerink note.
Amgen on Saturday also released data from two other ROCKET studies. The first, dubbed SHUTTLE, showed that rocatinlimab can elicit significant rates of EASI-75 when combined with topical corticosteroids or topical calcineurin inhibitors. The second, named VOYAGER, found that rocatinlimab does not interfere with response to tetanus and meningococcal vaccines.
