5. Niraparib

AstraZeneca's Lynparza and Clovis' Rubraca will be the key rivals when and if niraparib hits the market, but Tesaro is hoping a broad label will give its PARP inhibitor a bigger market to target.

Generic name: niraparib
Company: Tesaro
Disease: cancer
2022 sales estimate: $1.9 billion

Niraparib wouldn't be the first PARP-inhibiting drug on the market. That honor belongs to AstraZeneca's Lynparza. Nor would it be second, thanks to Clovis Oncology's early nod for Rubraca last month. But Tesaro is hoping that its entry will launch with a bigger target, thanks to study data showing it delivered benefits not only to women with the BRCA gene mutation, but those without.

In trial results unveiled at the European Society of Medical Oncology meeting last fall, the drug delivered a 15.5-month progression-free survival advantage over placebo in BRCA-mutated ovarian cancer, and a 5.4-month advantage in women without the mutation. In a subset of non-BRCA cancers—those that tested positive for a different abnormality—niraparib delayed cancer’s advance by 12.9 months, compared with 3.8 months in the control group, an improvement of more than 9 months.

"We have never seen such large benefits in progression-free survival in recurrent ovarian cancer,” the study's lead author, Dr. Mansoor Raza Mirza of Copenhagen University, said at the time. “Niraparib significantly improved all endpoints across a broad patient population representing 70% of all ovarian cancer patients.”

Tesaro wrapped up its rolling submission to the FDA in November, and it had already won the FDA's priority review status, giving it a speedier path through the agency. The FDA isn't planning an advisory committee meeting to discuss the application, which analysts see as a good sign. Leerink Partners analyst Seamus Fernandez recently said he has "high expectations for a broad label" when niraparib is approved. The drug's FDA decision date is June 30.

Niraparib will be first up for a second-line ovarian cancer nod, but Tesaro is studying the drug in previously untreated patients in hopes of a first-line approval as well. It's also putting niraparib through trials in breast cancer.

AstraZeneca's Lynparza and Clovis' Rubraca will be the key rivals when and if niraparib hits the market. The U.K. drugmaker has been touting data of its own as it prepares for a potential fight for market share. And Clovis has a bigger head start than it might have otherwise, thanks to the FDA's earlier-than-expected approval granted in December. If Tesaro's med wins a broader label than Lynparza, however, it'll also have Rubraca's label beat; the Clovis med is approved for BRCA-mutated cancers just as Lynparza is.

5. Niraparib