SAN ANTONIO—Roche is in the hot seat as its longtime breast cancer blockbuster Herceptin faces a growing stable of biosimilar challengers. But other drugs in Roche's portfolio are on the rise: Look at Perjeta, which aims to build its case as the add-on drug of choice for HER2-positive breast cancer patients.
Adding Perjeta to standard-of-care Herceptin and chemotherapy reduced the risk of recurrence and death by 24% over standard of care alone in HER2-positive early breast cancer patients after six years of treatment. Those data from an analysis of Roche's phase 3 Aphinity trial were presented Wednesday at the San Antonio Breast Cancer Symposium.
Perjeta showed the greatest clinical benefit in patients whose cancer had spread to the lymph nodes; 87.9% of that group was disease-free at the six-year mark, compared with 83.4% for the control arm.
For that cohort, the Perjeta arm showed a 28% relative risk reduction over standard of care alone, the analysis found.
The six-year analysis actually showed Perjeta outperformed in HER2-positive breast cancer patients after six years of treatment rather than three. In an earlier analysis at the three-year mark, Perjeta scored an 18% relative risk reduction over standard of care in the same population.
On the overall survival side, Perjeta didn't beat the Herceptin-plus-chemo combo, however—neither at the three-year nor the six-year mark.
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Still, the newest data could help Roche build Perjeta's case as an adjuvant treatment in HER2-positive breast cancer patients, an indication the FDA granted in late 2017.
In the first nine months of this year, Perjeta hit $2.6 billion in global sales, a 34% hike from the same time period in 2018.
Perjeta's success has coincided with a now-realized U.S. biosimilar threat to longtime blockbuster Herceptin and the rapid growth of Roche's next-gen breast cancer drug Kadcyla.
Earlier this month, Mylan launched its Herceptin copy, Ogivri, in the U.S., making it the second biosim to launch against the blockbuster so far. Amgen christened its own copy, Kanjinti, back in July.
Meanwhile, Kadcyla hit $1 billion in global sales in the first nine months of the year on staggering 40% growth. In May, the FDA approved Kadcyla for adjuvant treatment of HER-2 positive, early breast cancer patients who didn’t fully respond to drug therapy before surgery.