The US FDA has awarded Novartis’ Kisqali breakthrough designation (BTD) in the wake of a trial showing the drug is effective in treating breast cancer in younger women.
The BTD is based on the results of the MONALEESA-7 trial, which involved pre-menopausal women with hormone-receptor positive, HER2-negative advanced breast cancer and was the first to show that a CDK4/6 inhibitor can have a benefit in this setting.
In the study, giving Kisqali (ribociclib) in combination with tamoxifen or an aromatase inhibitor as initial endocrine-based therapy for women in this group significantly prolonged progression-free survival (PFS) compared to endocrine therapy alone, extending it from 13 months to almost 24 months.
If approved in younger women with advanced breast cancer, Kisqali could mount a bigger challenge against main marketplace rival Ibrance (palbociclib) from Pfizer, which was the first drug in the CDK4/6 blocker class to reach the market in 2015 and grew more than 60% to reach $2.4bn in sales in the first nine months of 2017.
Kisqali was approved last summer and had made $26m in sales by the end of the third quarter, so still has a long way to go to catch Ibrance. Meanwhile Novartis is trying to keep its new drug ahead of Eli Lilly’s CDK4/6 inhibitor Verzenio (abemaciclib), which was approved in the US – its first market – last September.
EvaluatePharma recently predicted that Ibrance will become a mega-blockbuster with sales of $6bn-plus in 2022, with Kisqali and Verzenio fighting for a distant second place. Meanwhile, Novartis has tried to take on Ibrance with a flexible pricing scheme as well as a co-packaged version of the drug with its endocrine therapy Femara (letrozole) in the US, which means patients can avoid a second co-pay.
“Younger women often have distinct treatment goals and needs, and it is important for oncologists to offer effective and well-studied treatment options for their specific disease,” commented Samit Hirawat, Novartis’ head of cancer drug development.
“We look forward to working with FDA to make this combination therapy available to premenopausal women living with HR+/HER2- advanced breast cancer in the US as soon as possible,” he added.
Premenopausal breast cancer is a biologically distinct and more aggressive disease than postmenopausal breast cancer, and it is the leading cause of cancer death among women in the 20-59 age bracket.