Why Genmab Stock Smashed It on Monday

On a generally upbeat Monday for the stock market, investors weren't only buying into U.S. companies. Quite a few of them also piled into the American Depositary Receipts (ADRs) of Danish biotech Genmab (NASDAQ: GMAB), on the back of encouraging news from the laboratory. Management's disclosure of the status of a shareholder-pleasing initiative also helped boost sentiment.

The price of those ADRs rose by almost 4% as a result -- quite a distance higher than the S&P 500's (SNPINDEX: ^GSPC) 0.4% advance.

Fresh news from the lab, and about the stock

On Monday morning, Genmab announced a set of phase 1/2 clinical trial results for its rinatabart sesutecan (Rina-S) drug, which it's developing for a type of uterine cancer. The company said the drug showed a confirmed objective response rate of 50% in patients with an advanced form of the cancer who had received treatment with other medications.

Image source: Getty Images.

In its press release detailing the results, Genmab quoted study investigator Ira Winer as saying that the results "demonstrate encouraging data with Rina-S in this patient population and support its further development as a potential therapy for patients with advanced and recurrent endometrial cancer."

The company added that, with this at its back, it aims to continue the development of the drug.

Separately, Genmab updated investors about its current share buyback program, which authorized the repurchase of up to 2.2 million shares of its Europe-listed stock by July 10 of this year. The company was quite an aggressive buyer, snapping up just under 2.08 million shares for a total of slightly more than 2.7 billion Danish kronor ($411 million).

More testing to be done

Taken together, those two news items suggest that Genmab is on the right path with its development activities, and believes in its pipeline. The proof with Rina-S, of course, will come with later-stage clinical trials. However, at this point, the company's future looks promising, and the bullish market reaction feels justified.

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Eric Volkman has no position in any of the stocks mentioned. The Motley Fool has positions in and recommends Genmab A/s. The Motley Fool has a disclosure policy.