ESMO: Novartis parses long-awaited survival data for breast cancer blockbuster hopeful Piqray

When Novartis won FDA approval for its breast cancer drug Piqray in HR-positive/HER2-negative patients with PIK3CA mutations last year, early survival data were impressive: Combining the drug with AstraZeneca’s Faslodex nearly doubled the time to disease progression or death to 11 months over Faslodex alone.

Now, the final survival data from that trial, called Solar-1, are out. And while the overall survival rate wasn’t quite as dramatic, Novartis sees reason to celebrate—particularly for one subset of very sick patients.

The Piqray-Faslodex combo boosted overall survival for patients in the trial by eight months over Faslodex alone—too small a difference to reach statistical significance, Novartis announced during the virtual meeting of the European Society of Medical Oncology.

But among patients with lung or liver metastases, overall survival improved by more than 14 months to a median of 37.2 months.

“That was really impressive and very clinically meaningful,” Jeff Legos, senior vice president and and head of oncology drug development at Novartis, said in an interview. “Patients with advanced breast cancer who have had their disease metastasize to the lung or liver generally do much worse on available therapy. I think this further reiterates the benefit [Piqray] can provide.”

The data showed that overall, patients taking Piqray plus Faslodex had a 14% lower risk of disease progression or death—a number that might not look that impressive on the surface, Legos acknowledged.

“But what’s also important for patients is their median overall survival," he said. "Here we show that patients are living on average eight months longer, which gives them that much more time to spend with family and friends and celebrate milestones.”

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Novartis hopes the new data will help elucidate some key points of the marketing pitch for Piqray. One of those is quality of life. Patients in the trial taking the Piqray-Faslodex combination were able to delay chemotherapy by a median time of 23.3 months, versus 14.8 months for the patients taking Faslodex alone. Although the combination did produce some side effects—hyperglycemia was the most common complaint—toxicity overall was lower than it typically is for patients on chemotherapy, Legos said. “So they had eight-and-a-half months of a higher quality of life,” he said.

Novartis was also able to parse the data from the trial using a biomarker called circulating tumor DNA. When a patient’s tumors are shedding so much of their genetic material that the cancer can be detected in blood, that’s a sign of aggressive disease and a poor prognosis, Legos said.

In patients who had detectable circulating tumor DNA at the start of the trial, Piqray plus Faslodex reduced the risk of death by 26%. “It’s just more evidence that there are patients who definitely are underserved with existing therapy and that [Piqray] does demonstrate a survival advantage,” Legos said.

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Novartis has often cited Piqray as a likely blockbuster. There are other PIK3 inhibitors on the market, including Verastem Oncology’s Copiktra and Gilead’s Zydelig, but Piqray was the first to gain a breast cancer nod.

Novartis has an ambitious development plan for the drug going forward. It’s preparing to file for approval in patients with a rare disorder called PIK3CA overgrowth syndrome. Novartis is also hoping to move the drug into triple-negative and HER2-positive breast cancers as well as ovarian and head and neck cancers.

Piqray brought in sales of $79 million in the second quarter of this year, up from $74 million in the previous quarter. The European Commission approved Piqray in July, and analysts are expecting total sales to surpass $700 million in 2024, according to EvaluatePharma. Moody’s predicts sales will peak at $1 billion a year.

Piqray’s first FDA nod came courtesy of the agency’s Real-Time Oncology Review program—a boon for Novartis, Legos said. “The overall submission and review cycle was incredibly fast,” he said. “As soon as data became available we were able to share it with the FDA and engage with them. It was a collaborative relationship, with the patient in mind.”