|
By Cormac Sheridan
BioWorld Today Correspondent
Shares in Genmab A/S slid more than 20 percent Monday on news that zalutumumab, an antibody-targeting epidermal growth factor receptor (EGFR), failed to reach the primary endpoint of a pivotal Phase III trial in head and neck cancer.
The Copenhagen, Denmark-based company reported that patients who received the drug plus best supportive care attained a median survival of 6.7 months, while those on best supportive care alone attained a median overall survival of 5.2 months. However, the result was not statistically significant (p = 0.0648).
The drug did better on a secondary endpoint.
Patients in the drug treatment arm achieved a 61 percent increase in progression-free survival compared with those in the comparator arm (p = 0.0010).
Widespread deviations from the trial protocol may have affected the final result.
The company said that 28 percent of patients in the comparator arm (n = 95) and 14 percent of those in the drug treatment arm (n = 191) received anticancer therapies that were not permitted by the protocol.
The median time to first use of other drugs was 79 days in the supportive care arm and 170 days in the zalutumumab arm.
"These additional treatments are likely the result of patients having very serious disease and short life expectancy," Genmab CEO Lisa Drakeman told analysts on a conference call.
The company will analyze the data and seek external advice before deciding on its next steps for the drug - if any. "Our immediate job is going to be to take a look at what the opinion leaders are going to have to say," Drakeman said.
Several cancer drugs gained approval in Europe on the basis of surrogate endpoints, she noted.
"We believe we have shown here that the drug is clinically active," said Genmab Chief Scientific Officer Jan van de Winkel.
Convincing the FDA of the drug's efficacy will be more difficult, given its dislike of surrogate endpoints. Besides, Erbitux (cetuximab), another EGFR inhibitor, is already approved in the same indication. That drug is marketed by Bristol-Myers Squibb Co., of New York, and ImClone Systems Inc., a subsidiary of Eli Lilly and Co., of Indianapolis.
Analysts were skeptical about zalutumumab's prospects. "It hasn't a future," Lars Hatholt at Nordea Markets in Copenhagen told BioWorld Today. "The survival extension data weren't good enough."
"I don't think the company will be able to file with the current data," Gustaf Vahlne at SEB Enskilda in Stockholm, Sweden, told BioWorld Today. The company - or a partner - would need to perform a head-to-head study against Erbitux.
"That of course would be very time-consuming," Vahlne said. And the outcome would not be guaranteed. "I'm not sure if Genmab would like to take that risk," he said.
But there are still some outstanding questions that need answers. "We would like to see the per-protocol data," Vahlne said.
The company is funded through the next three years, assuming that it can raise a targeted DKK750 million (US$137 million) from the disposal of a U.S. manufacturing facility in Brooklyn Park, Minn. Its financial guidance for the current year is not affected by the news.
Shares in Genmab (COPENHAGEN:GEN) closed Monday at DKK73.50, having closed on Friday at DKK92.35.
| 
