By Mary Welch
Characterizing the news as "not a surprise," British Biotech plc said that a Phase III study of marimastat in patients with glioblastoma failed to show a statistically significant advantage over the placebo in either the primary or secondary endpoint.
"Obviously we're disappointed and we're disappointed for glioblastoma patients but it was not surprising," said Tony Weir, finance director for the Oxford, UK-based company. "If you look back at marimastat and the studies we've done or are doing, it's quite clear that marimastat doesn't do well when the chances of survival of the patients were relatively low. Glioblastoma is a very advanced disease. Marimastat doesn't have time to work in order to make an impact. In addition, the study was underpowered in the patient population."
The Phase III trial involved 162 patients with glioblastoma, which is a form of brain cancer. Half of the patients received marimastat, the other half a placebo.
This was not the first failure for marimastat. The oral anticancer drug earlier this year tanked in a Phase III trial for pancreatic cancer. It also failed to show a statistical benefit in gastric cancer.
There are three more Phase III studies under way with marimastat. One study for small-cell lung cancer involves 360 patients; the other study for the same indication involves 540 people. There also is a trial ongoing with ovarian cancer patients.
"We are not expecting positive results from the study with ovarian cancer basically for the same reasons why this trial's results were not a surprise," Weir said. "However, the trials for small-cell lung cancer are powered and they involve patients with less-advanced disease. In addition, there is a large subset who have limited disease who underwent chemotherapy or surgery."
British Biotech is betting the farm on the success of this trial.
"From what we know, this is the drug's best chance for success," Weir said. "It will, in fact, determine its future. It will determine whether we move for a filing or, after discussions with Schering-Plough, terminate the project."
Results from all three trials are expected before the new year, he said.
Marimastat is an oral matrix metalloproteinase (MMP) inhibitor. It is a broad-spectrum agent with inhibitory action against the known classes of MMP enzymes implicated in breaking down tissues that surround malignant tumors, an important factor in cancer growth and spread. Marimastat, theoretically, should prevent tissue breakdown and contain the malignancy.
The company entered last year into a $60 million deal with Schering-Plough Corp., of Madison, N.J., to develop and commercialize marimastat as well as other MMP inhibitors. (See BioWorld Today, Sept. 8, 1999, p. 1.)
British Biotech's stock (NASDAQ:BBIOY) closed Friday at $3, down 50 cents, or 14.29 percent. The stock was trading at more than $8 in January before disclosure of the negative results in pancreatic cancer.