Genmab is having a tough day on the stock market on Wednesday after partial data from a phase III trial of Mariposa for lung cancer showed disappointing results.

Although the results are positive in themselves, they are ”not as good as hoped” nor ”strong enough” to match the existing standard in the market, according to the stock exchange house Cowen, Bloomberg reports.

At US investment bank Jefferies, analyst Peter Welford sees a possibility that the ”mixed” results could pose a ”competitive” threat to AstraZeneca’s drug, Tagrisso (osimertinib).

Genmab’s study was conducted in collaboration with partner Johnson & Johnson.

Mariposa is a combination of Genmab’s lung cancer drug, Rybrevant (amivantamab), and the active ingredient lazertinib, developed by Johnson & Johnson.

In the study, Mariposa was compared to AstraZeneca’s drug, Tagrisso, which is considered the standard of care for lung cancer treatment. The results will be announced at a pharmaceutical conference at a later date.

Although the Mariposa results are unlikely to affect Tagrisso’s market position, Genmab’s Rybrevant is ”very attractive” as a potential second-line treatment, analyst Asthika Goonewardene of Truist Securities wrote in a note, the media reports.

Primary endpoints reached

The results from the phase III study with Mariposa were announced on Sept. 28 and appeared in Johnson & Johnson’s third-quarter results released on Tuesday.

In the press release, the US pharmaceutical company states that the combination of Rybrevant and lazertinib showed a statistically significant and clinically meaningful improvement in patients with cancer without worsening the disease compared to the agent osimertinib in AstraZeneca’s Tagrisso.

Thus, the study met its primary endpoint.

Genmab plunges 6.6% to DKK 2124 on Wednesday. The share is further weighed down by the fact that French BNP Paribas has initiated coverage of the company with a negative recommendation of ”underperform” and a price target of DKK 2,000 (USD 283.2).

(Translated by DeepL with additional editing by Christian Radich Hoffman)