Roche's PI3K Blocker for Breast Cancer Approved, Projects $2.3B Peak Sales

With the recent FDA approval for advanced breast cancer, Roche's inavolisib, now branded as Itovebi, emerges as a strong competitor to Novartis' PI3K inhibitor Piqray, which garnered $505 million in revenue last year.

On Thursday, the FDA sanctioned Roche's Itovebi for first-line treatment in specific breast cancer patients, in combination with Pfizer’s Ibrance and AstraZeneca’s Faslodex. The approved regimen is intended for adult patients with endocrine-resistant, PIK3CA-mutated, HR-positive, and HER2-negative locally advanced or metastatic breast cancer. Notably, this approval was granted more than a month earlier than the original target date of November 27.

Levi Garraway, Roche's Chief Medical Officer, stated that the approval of Itovebi provides "an important new first-line option" for patients with HR-positive breast cancer carrying the PIK3CA mutation. Garraway emphasized the significance of this approval due to the limited treatment options available for this prevalent mutation.

The decision to approve Itovebi was based on data from the Phase III INAVO120 study, a randomized, double-blinded, placebo-controlled trial that assessed the combination regimen against Ibrance and Faslodex paired with a placebo. In December 2023, Roche reported results from the INAVO120 study, highlighting a 57% reduction in the risk of disease progression or death in patients treated with Itovebi compared to the placebo group. This result was statistically significant with a p-value less than 0.0001.

Although the overall survival data were still immature at the time of primary analysis, there was a "clear positive trend" favoring the Itovebi treatment group. In terms of safety, the INAVO120 study found that the Itovebi combination was well-tolerated, with adverse events aligning with the toxicity profiles of the individual therapies. The dropout rate for the Itovebi group was 6.8%, compared to 0.6% in the placebo group.

Garraway remarked that these findings suggest that the Itovebi regimen has the potential to become a new standard of care for this patient demographic. He noted that by targeting the PI3K pathway, inavolisib could revolutionize the treatment of breast cancer in patients whose tumors harbor PIK3CA mutations.

Itovebi is an orally administered small molecule that inhibits the PI3K protein, which plays a crucial role in cell growth, proliferation, differentiation, and survival. Its mechanism of action involves suppressing tumor growth, and when used in combination with Ibrance and Faslodex, it can produce a more potent anti-cancer effect compared to each treatment alone or in double combinations.

With the recent FDA approval, Roche enters the PI3K inhibitor market, challenging Novartis, whose oral drug Piqray (alpelisib) was approved by the FDA in 2019 for the same indication. Piqray generated $505 million in revenue in 2023.

Teresa Graham, CEO of Roche Pharmaceuticals, has projected Itovebi’s peak sales potential to reach $2.3 billion.