Genmab shares jump 13% on colorectal cancer drug trial results

What happened: Genmab shares rose as much as 13% after the Danish biotech said petosemtamab plus chemotherapy shrank tumours in 75% of evaluable previously untreated patients with advanced colorectal cancer in a mid-stage trial. Key numbers: 75% first-line response rate, 67% second-line, 81% in left-sided first-line tumours, 95% first-line disease control, 79 patients treated as of May 15, 2026 (45 Why it matters: Genmab's chief medical officer said the results provide a compelling rationale for its ongoing Phase 3 trials in first- and second-line RAS/BRAF wild-type colorectal cancer.

Genmab shares rose as much as 13% after the Danish biotech said petosemtamab plus chemotherapy shrank tumours in 75% of evaluable previously untreated patients with advanced colorectal cancer in a mid-stage trial.

Genmab's chief medical officer said the results provide a compelling rationale for its ongoing Phase 3 trials in first- and second-line RAS/BRAF wild-type colorectal cancer.