Double Good News For AstraZeneca's Breast Cancer Drugs

AstraZeneca plc (NASDAQ:AZN) reported topline data from a metastatic breast cancer treatment study.

The results showed that Enhertu (trastuzumab deruxtecan) demonstrated a statistically significant and clinically meaningful improvement in progression-free survival (PFS) compared to standard-of-care chemotherapy in the primary trial population of patients with HR-positive, HER2-low (IHC 1+ or 2+/ISH-) metastatic breast cancer following one or more lines of endocrine therapy.

A statistically significant and clinically meaningful improvement in PFS was also observed in the overall trial population (patients with HER2-low and HER2-ultralow [defined as IHC 0 with membrane staining; IHC >0<1+] metastatic breast cancer). 

Related: AstraZeneca Posts Bumper Earnings On Strong Sales From Cancer Drugs, Sticks To Annual Guidance.

A prespecified subgroup analysis showed that clinically meaningful improvement was consistent between patients with HER2-low and HER2-ultralow expression.

Overall survival (OS) data were not mature at the time of the analysis. However, Enhertu showed an early trend towards an OS improvement. It was compared to standard-of-care chemotherapy in patients with HER2-low metastatic breast cancer and the overall trial population. 

The trial will continue to assess OS and other secondary endpoints further.

Enhertu is a HER2-directed DXd antibody-drug conjugate discovered by Daiichi Sankyo (OTC:DSKYF) (OTC:DSNKY) and is being jointly developed and commercialized by AstraZeneca and Daiichi Sankyo.

Concurrently, AstraZeneca's Truqap (capivasertib) in combination with Faslodex (fulvestrant) has been recommended for approval in the European Union for adult patients with estrogen receptor (ER)-positive, HER2‑negative locally advanced or metastatic breast cancer with one or more PIK3CA, AKT1, or PTEN-alterations following recurrence or progression on or after an endocrine-based regimen.

The Committee for Medicinal Products for Human Use of the European Medicines Agency based its opinion on the CAPItello-291 Phase 3 trial results.

Truqap in combination with Faslodex reduced the risk of disease progression or death by 50%. Compare that to Faslodex alone in patients with tumors harboring PI3K, AKT, or PTEN alterations (based on a hazard ratio of 0.50, p=<0.001; median PFS 7.3 versus 3.1 months).

Price Action: AZN shares are up 1.65% at $76.41 during the premarket session at the last check Monday.