Glaxo's Cervarix probably won't reach the U.S. market until sometime in 2007, assuming it is approved by regulators, while the first cervical-cancer vaccine, Merck & Co.'s (MRK) Gardasil, went on sale in the U.S. in June. A government advisory committee has recommended Gardasil for girls and women ages 11 to 26, and analysts expect sales to top $1 billion within a few years. More drugs in development at Drug Pipeline
Despite Merck's head start, Glaxo executives said in interviews this week that they like Cervarix's prospects because they think it will be more effective in preventing cervical cancer, and will carry a simpler marketing message than Gardasil's.
"I just think we flat out have a superior product," David Pernock, senior vice president of pharmaceuticals, said in an interview Tuesday in his office at Glaxo's North American headquarters in Philadelphia.
Of course, such claims must be backed by science. To that end, Glaxo expects to receive data from a large-scale, Phase III trial of Cervarix by the end of this month, Pernock said. The company plans to submit the data to the U.S. Food and Drug Administration by the end of the year. An FDA decision on whether to approve Cervarix is expected no later than 10 months after application.
Both Gardasil and Cervarix target two strains of the sexually transmitted human papillomavirus, or HPV, that are associated with about 70% of cervical cancer cases. The vaccines haven't been compared head-to-head in clinical trials.
But Glaxo executives highlight several differences. Cervarix includes a proprietary additive, known as an adjuvant, while Gardasil uses a more conventional aluminum-based adjuvant. Glaxo says its proprietary adjuvant produces a more enhanced immune response to the virus than a conventional adjuvant.
David Stout, president of Glaxo's pharmaceutical operations, said in a separate interview Tuesday that Cervarix may provide "cross-protection" against additional cancer-causing strains of HPV, which could bring the protection rate up to 80% of cervical cancer cases. Stout also hopes Cervarix will offer longer-lasting protection against HPV, potentially reducing the frequency of booster shots.
Mark Feinberg, vice president of policy, public health and medical affairs with Merck's vaccines unit, counters that while adjuvants are important, the clinical benefits are what matters, and Gardasil's are solid. Also, he said, Gardasil and Cervarix target the same strains of HPV, so any cross-protection found in Cervarix would likely be seen in Gardasil, too. He said Merck is studying Gardasil's cross-protection potential.
"The data from studies of Gardasil are very clear in terms of not only the magnitude of the benefit and breadth of the benefit, but also we have data demonstrating the duration of the benefit out to five years with a very persistent high level of immune response," Feinberg said in an interview Wednesday. He called Glaxo's clinical data for Cervarix "limited."
In large Phase III studies, Merck's Gardasil was 100% effective in preventing precursors to cervical cancer and noninvasive cervical cancers associated with two of the HPV strains targeted by the vaccine. Merck's data suggest the protection lasts for at least five years.
Smaller, earlier-stage studies of Cervarix have shown it to be 100% effective in preventing precancerous lesions associated with the same two cancer-causing strains of HPV. Glaxo said the protection was sustained for four-and-a-half years.
Another difference between the vaccines is that Gardasil protects against two additional HPV strains associated with genital warts, a less serious but painful condition. Cervarix targets only the two strains associated with cervical cancer, and Glaxo has suggested this could make its marketing message more focused.
"We'll focus on preventing cervical cancer," Pernock said.
But Feinberg says the HPV strains associated with genital warts also can lead to abnormal results in Pap tests, which are used to screen for cervical cancer. By protecting against these two additional strains, Gardasil may reduce abnormal Pap test results and unnecessary follow-up care. In addition, a vaccine that protects against genital warts may appeal to boys and men, who can get these warts. If males were to take the vaccine, that could help reduce the spread of HPV, thus reducing the incidence of cervical cancer in women. Gardasil hasn't yet been approved for use in males, however.
The Glaxo executives said Merck's head start doesn't guarantee Gardasil will outperform Cervarix in the long run, pointing to other examples of first-in-class products being outsold by later competitors. "Lipitor was not the first statin," Stout said, referring to Pfizer Inc.'s (PFE) cholesterol-lowering pill, which is now the best-selling drug in the world.
Stout noted that Merck, with its "Tell Someone" advertising campaign, is now doing the heavy lifting of educating consumers about HPV and vaccines, which could make Glaxo's job easier once Cervarix is launched. Feinberg says Merck's marketing campaign is "addressing a number of issues about vaccine implementation...In our mind, those are essential things to do."
Ironically, Glaxo will profit directly from Gardasil - Merck is paying it royalties under terms of a February 2005 settlement of the companies' competing patent claims for their respective vaccines. Under the settlement and license agreement, Merck was to make an up-front payment to Glaxo and pay ongoing royalties on Gardasil's sales.
Merck, of Whitehouse Station, N.J., disclosed last month it will have to pay royalties on Gardasil totaling about 24% to 26% of sales, including payments to Glaxo. The royalties also include payments to CSL Ltd. (CSL.AU) of Australia. Merck didn't break out the portion of the royalties going to Glaxo.
Pernock said Glaxo's royalties for Cervarix won't be as high, but he declined to specify the percentage.
Glaxo might try to speed up the launch of Cervarix by a few months. Stout said Glaxo may try to convince the FDA to give Cervarix priority-review status, which would shorten the review period to six months from the standard 10 months. The FDA typically grants priority-review status only to products that have evidence of being more effective than what is already available on the market, and Gardasil received such status. "We must demonstrate ours is not just similar but significantly better," Stout said. "We hope to do this."
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