Talazoparib before surgery for patients with BRCA mutated breast cancer

This study aimed to investigate the effectiveness and safety of talazoparib as a neoadjuvant agent (treatment before surgery) in patients with BRCA mutation and operable breast cancer. 

This study concluded that this treatment was a safe and effective in these patients.  

A neoadjuvant treatment is used to shrink the tumor before the main treatment, usually surgery.  

Talazoparib (Talzenna) is a type of targeted therapy called a PARP inhibitor. It is used for the treatment of advanced cancer which is BRCA mutation-positive (abnormal gene) and HER2 negative. PARP inhibitors block DNA repair and cause cancer cells to die. BRCA mutation is a mutation in BRCA1 or BRCA2 gene which are tumor suppressor genes. If these genes are mutated, they do not work to suppress tumors. This leads to tumor growth 

It was unknown if talazoparib would be safe and effective as a neoadjuvant treatment in patients with operable breast cancer (BC) that was BRCA mutation-positive.

This study involved 20 patients with BRCA mutation-positive and operable BC. 75% of patients had triple-negative BC and 25% had hormone receptor-positive BC. Patients received talazoparib once per day for 6 months as a neoadjuvant treatment. Patients then had surgery to remove the tumor.  

Residual cancer burden (RCB-0) was the main outcome measured. RCB-0 is when no signs of cancer can be seen after surgery. The RCB-0 rate was 53% and RCB-0/I rate was 63%.  

40% of patients experienced severe anemia (low red blood cells) as a side effect. These patients required a blood transfusion. 15% experienced severe neutropenia (low white blood cells). 1 patient experienced life-threatening thrombocytopenia (low blood platelet count). Mild to moderate side effects included nausea, fatigue, neutropenia, hair loss, dizziness and shortness of breath. Side effects were managed by dose reduction and transfusions. 9 patients required dose reductions.  

This study concluded that talazoparib was a safe and effective neoadjuvant treatment for patients with BRCA-positive operable BC. 

This was a very small study. Further larger studies are needed. This study received support from Pfizer, the manufacturer of talazoparib.