In 2014, the FDA approved the first (adenosine diphosphate-ribose) polymerase (PARP) inhibitor AstraZeneca/Merck’s Lynparza (olaparib) for use in breast cancer gene (BRCA)-mutated metastatic ovarian cancer patients who have received three or more prior lines of chemotherapy. Since then, the PARP inhibitors market has made significant strides, but Lynparza maintains its dominance with projected global sales of $4 billion by 2027, according to an analyst consensus forecast by GlobalData.

GlobalData’s analyst consensus reveals that high sales projections underscore Lynparza’s role in treating multiple cancer types, including ovarian, pancreatic, prostate, and human epidermal growth factor receptor 2 (HER2)-negative breast cancer. Expected revenues in these indications will reach over 68 per cent of the global PARP inhibitors market by 2027. GlaxoSmithKline’s (GSK) Zejula (niraparib) holds the second position with over $1.6 billion in sales and 28 per cent of the market share. Most of Lynparza’s sales come from ovarian and HER2-negative breast cancer treatment.

Biswajit Podder, Oncology and Hematology Analyst at GlobalData, comments, “Amidst this progress, AstraZeneca and Merck voluntarily withdrew approval for Lynparza in BRCA-mutated advanced ovarian cancer patients who have received at least three prior lines of chemotherapy. As Lynparza’s patent protection in the US market will expire in 2028, there is an anticipated downshift in sales post-patent expiry through generic erosion.

“However, AstraZeneca’s new selective PARP1 inhibitor, saruparib, shows early promise in Phase I/II trials for homologous recombination repair (HRR)-deficient advanced breast cancers, with a good safety and efficacy profile, and it can cross the blood-brain barrier. If approved, saruparib would further strengthen AstraZeneca’s lead in the PARP inhibitor market.”

Lynparza’s growing application across multiple cancer types, driven by ongoing 123 Phase I-III clinical trials, signifies its pivotal role in oncology. In May 2023, the FDA approved Lynparza and Johnson & Johnson’s Zytiga (abiraterone) for treating patients with deleterious or suspected deleterious BRCA-mutated metastatic castration-resistant prostate cancer as determined by an FDA-approved companion diagnostic test, despite AstraZeneca and Merck’s voluntary withdrawal for BRCA-mutated advanced ovarian cancer.

Podder concludes, “The right patient selection for treatment with PARP inhibitors, either as monotherapy or in combination with other agents, remains an unmet need in the clinic. Lynparza should be used with reliable biomarkers to select patients most likely to respond to the therapy, especially those with HRR deficiency or other DNA repair defects, irrespective of their BRCA mutation status. AstraZeneca and Merck should emphasise the use of these biomarkers in clinical trials to improve patient stratification and achieve better outcomes.”