Genmab shares jumped 13.7 percent in European trading on Monday as investors reacted to Friday’s ESMO readouts: a Phase 3 ovarian cancer win for rinatabart sesutecan and updated Phase 2 colorectal data for petosemtamab.
Genmab shares jumped 13.7 percent in European trading on Monday to the top of the STOXX index, as investors reacted to two cancer readouts the Danish biotechnology company released on Friday at the European Society for Medical Oncology congress in Madrid.
The larger of the two readouts came from the Phase 3 RAINFOL-02 trial of rinatabart sesutecan, known as Rina-S, in platinum-resistant ovarian cancer. In the intent-to-treat population of 584 patients, Rina-S cut the risk of disease progression or death by 71 percent, a hazard ratio of 0.29, and cut the risk of death by 57 percent, a hazard ratio of 0.43. Genmab reported no new safety signals in the trial.
The second readout was updated follow-up from a Phase 2 trial of petosemtamab, an investigational antibody targeting EGFR and LGR5, given with chemotherapy in metastatic colorectal cancer. Confirmed and unconfirmed objective response rates were 75 percent in the first-line setting and 67 percent in the second-line setting, rising to 81 percent among first-line patients with left-sided tumours, at median follow-up of 5.9 and 7.1 months respectively. The analysis covered 79 patients, with disease control rates of 95 percent in the first-line setting and 93 percent in the second-line setting, and Genmab said the data support its ongoing global Phase 3 programme.
Genmab’s own releases confirm the figures for both trials. One point of attribution needs care: Reuters credited Monday’s share jump to the colorectal data, while Dow Jones and Bloomberg credited it to the ovarian Rina-S data. Both datasets were released on Friday, so Monday’s trading reflected the pair of readouts together, not a single announcement made on Monday. The wider STOXX 600 index rose 0.4 percent to 638.45 points by 1050 GMT, which puts Genmab’s move well ahead of the market.
The next checkpoint is an investor update on October 28, flagged in trade coverage of the Rina-S results. For petosemtamab, the question is whether the response rates hold up in the larger Phase 3 trials now enrolling, and for Rina-S, whether the survival benefit translates into the next stage of the drug’s development.