Arvinas gets a degrader delay

Last month Arvinas raised the possibility of a delay to the Veritac-2 trial of its Pfizer-partnered SERD vepdegestrant, and it has confirmed this at the Jefferies London healthcare conference. The study, in second-line ER-positive, HER2-negative breast cancer, had once been expected to read out this year, but data are now due in early 2025 – likely February, Arvinas disclosed on Tuesday. As with all SERDs, one question will be whether vepdegestrant can show a benefit in all comers, not just in ESR1 mutants. The latter population is where Menarini’s Orserdu, the only approved SERD, is indicated. Arvinas execs noted that 40-50% of patients in Veritac-2 had ESR1 mutations; the trial is testing PFS in this subgroup and in all comers. Lilly recently disclosed that the second-line Ember-3 study of its rival agent, imlunestrant (with or without Verzenio), had succeeded and that data would be presented at the San Antonio Breast Cancer Symposium in December. The Arvinas execs cautioned against comparing Veritac-2 against Ember-3, not least because vepdegestrant’s trial requires patients to have been treated with a CDK4/6 inhibitor, while imlunestrant’s doesn’t. At SABCS, investors will therefore be looking for details on how CDK4/6-naive and experienced patients fare on imlunestrant.