When the Pallas study of Pfizer’s Ibrance failed in high risk early breast cancer at the beginning of the month, expectations around Eli Lilly’s similar trial of Verzenio, MonarchE, plunged. Surprise all round today when an interim analysis from MonarchE showed that adding Verzenio to standard adjuvant endocrine therapy significantly decreased the risk of recurrence or death, over hormone therapy alone. The actual benefit remains important to know however Lilly described the results as definitive. The company's decision to enrol patients with relatively severe disease – at least four lymph nodes positive or 1-3 nodes positive plus either tumours greater than 5cm in size, grade 3 histology or high risk of recurrence – has paid off. Pfizer enrolled a broader population in Pallas, hoping for a bigger ultimate market, but the likeliest outcome now is that Verzenio will be the first CDK 4/6 to market, probably next year, with any sort of early breast cancer indication. The Penelope-B trial of Ibrance, again in a broad group, is still running with data expected later this year. Lilly’s shares surged 13% in early trade, adding a huge $18bn to the company's market cap.
|Selected trials of CDK 4 & 6 inhibitors in early breast cancer|
|Group||Drug||Trial||Details||N||Results||2026e BC sales ($m)|
|Lilly||Verzenio||MonarchE||Verzenio + ET vs. ET alone in resected node-positive, early stage HR+, HER2- invasive BC||4,580||Interim hit on recurrence or death||2,596|
|Pfizer||Ibrance||Pallas||Ibrance for 2 years + ET vs. ET alone in HR+/HER2- stage II or III early invasive BC||5,794||Stopped for futility||11,036*|
|Pfizer||Ibrance||Penelope-B||Ibrance + ET in HR+/HER normal patients with residual disease after neoadjuvant chemotherapy and surgery||1,250||Expected early 2021||11,036*|
|Novartis||Kisquali||Natalee||Kisqali + ET or ET alone in patients with stage II or III HR+/HER2- early BC||4,000||2025||1,470|
|ET=endocrine therapy; BC=breast cancer. * Forecasts predate Pallas halt for futility. Source: EvaluatePharma, clinicaltrials.gov.|