Roche is looking to augment sales of its newer cancer drugs as biosimilars of its older cash cows near the market, and it took another step toward doing just that with Perjeta.
The FDA prioritized a combination marrying Perjeta to Roche’s mainstay breast cancer med Herceptin, for use in HER2-positive early breast cancer after their tumors have been surgically removed. The quick review could put the new combo in Roche’s marketing quiver by Jan. 28.
Treating cancer patients early on in their disease has been a goal for Roche—and other cancer drugmakers, too—because a higher number of those women are in line for therapy. Roche also argues that catching breast cancer early is more effective at combating the disease.
But in this case, there are questions about just how effective the Herceptin-Perjeta combo is, thanks to the Aphinity trial, which compared the partners, added to chemo, against Herceptin and chemotherapy alone.
In data rolled out at the American Society of Clinical Oncology meeting in June, the Aphinity trial showed that, at a three-year follow-up, 94.1% of those in the combo arm hadn’t developed an invasive form of HER2-positive disease. But 93.2% of women taking Herceptin with chemo hadn’t, either. The difference disappointed analysts, and could well disappoint oncologists, too.
Roche pointed out that the one-percentage-point margin was more significant than it seemed: It translated into a 19% lower chance of developing invasive breast cancer. At an ASCO investor event—which Bernstein analyst Tim Anderson dubbed “damage control”—Memorial Sloan Kettering Cancer Center’s Jose Baselga, a “well-respected breast cancer key opinion leader,” called that difference “very meaningful, on par with many other cancer therapies,” Anderson wrote.
But Aphinity isn’t over. Roche is still tracking those patients and will for a total of 10 years. The data are “far from mature,” Baselga said at the time. “[H]e is confident—based on the experience with prior HER2-positive trials—that the benefit will get better,” Anderson noted.
With Roche facing near-term biosim rivals to its best-selling Rituxan in addition to Herceptin, the Swiss drugmaker needs its newer meds to fill the gap. In July, an FDA advisory panel backed two Herceptin biosimilars, one from Amgen and Allergan, and the other from Mylan. Two Rituxan biosims are also under review; Roche is hoping its follow-up med Gazyva can take up where Rituxan left off.
That’s not to say Perjeta itself can’t grow significantly without a big uptake of the combo therapy in postsurgery patients. In numbers compiled in January, the market intelligence firm EvaluatePharma pegged Perjeta’s 2022 sales at $4.73 billion, up from about $1.9 billion last year, when it turned in growth of 26%. And also according to Evaluate, Herceptin and Rituxan will still be turning in major blockbuster sales that year, too.