AstraZeneca/Merck has unveiled new positive data for its PARP inhibitor Lynparza in ovarian cancer – as has its rival from GlaxoSmithKline, Zejula.
The new data was presented over the weekend at the European Society of Medical Oncology (ESMO) taking place in Barcelona, with AZ/Merck facing off with GSK in the PARP inhibitor category.
PARP inhibitors came to market on the strength that they can destroy BRCA-mutated tumours through synthetic lethality. However, both AZ/Merck and GSK have revealed positive data in their respective studies regardless of patients’ genetic status.
AZ/Merck’s Lynparza (olaparib) has been the lead in the PARP inhibitor category since the two pharma companies began co-developing the drug in 2017 via a deal worth $1.6bn upfront.
In August, the two companies revealed the top-line findings from the phase 3 PAOLA-1 trial, which showed that Lynparza in addition to Avastin (bevacizumab), the standard of care for ovarian cancer, produced a statistically significant increase in progression-free survival (PFS).
The detailed data presented at ESMO reveals by how much. PFS improved to a median of 22.1 months for those treated with the Lynparza combo compared to 16.6 months on Avastin alone.
It also reduced the risk of disease progression or death by 41% and at the two-year timepoint, 46% of women treated with the Lynparza combo showed no disease progression compared to 28% of those on the Avastin arm.
“The results showed at two years nearly half of women with advanced ovarian cancer were progression-free with Lynparza added to Avastin as a first-line maintenance treatment, regardless of their biomarker status or surgical outcome,” said José Baselga (pictured below), executive vice president, Oncology R&D at AstraZeneca.
José Baselga
“We are working with regulatory authorities to bring Lynparza to these patients as quickly as possible,” he added.
However, GSK also brought positive findings for Zejula (niraparib) in ovarian cancer, with the potential benefit that it is a monotherapy. Also revealing data at ESMO, GSK announced the results from its PRIMA phase 3 study of its PARP inhibitor in first-line ovarian cancer.
Treatment with GSK’s PARP inhibitor resulted in a 38% reduction in the risk of disease progression or death, in women regardless of tumour mutation type. According to GSK, the interim analysis of overall survival was also encouraging.
GSK could carve out a corner of the market on the strength of this data, but it is unlikely to make much headway on Lynparza, which dominates in the market. In its most recent results, AZ recorded Lynparza sales of $283m, with a new approval in ovarian cancer regardless of mutation likely to bolster the drug even further.
Also looking to carve a piece of the PARP inhibitor market in ovarian cancer is AbbVie, who also revealed positive data in this therapy area with its candidate veliparib. Although it produced postive results in PFS, it is unlikely that it can compete with the more establihsed contenders from GSK and AZ/Merck.