Talazoparib (BMN 673) demonstrates excellent potency, inhibiting PARP1 and PARP2 enzyme activity. It inhibits PARP-mediated PARylation in a whole-cell assay and prevents proliferation of cancer cells carrying mutant BRCA1/2. Talazoparib is orally available, displaying favorable pharmacokinetic properties and remarkable antitumor efficacy in the BRCA1 mutant MX-1 breast cancer xenograft model following oral administration as a single-agent or in combination with chemotherapy agents such as temozolomide and cisplatin. Medivation (a subsidiary of Pfizer) is developing talazoparib (MDV 3800, formerly BMN 673 and LT 673) for the treatment of genetically defined cancers. On October 16, 2018, the FDA approved talazoparib (TALZENNA, Pfizer Inc.) for patients with deleterious or suspected deleterious germline BRCA-mutated (gBRCAm), HER2‑negative locally advanced or metastatic breast cancer.

Amiodarone is an antiarrhythmic with mainly class III properties, but it possesses electrophysiologic characteristics of all four Vaughan Williams classes. Like class I drugs, amiodarone blocks sodium channels at rapid pacing frequencies, and like class II drugs, amiodarone exerts a noncompetitive antisympathetic action. In addition to blocking sodium channels, amiodarone blocks myocardial potassium channels, which contributes to slowing of conduction and prolongation of refractoriness. It is indicated for initiation of treatment and prophylaxis of frequently recurring ventricular fibrillation and hemodynamically unstable ventricular tachycardia in patients refractory to other therapy. The most common adverse reactions (1-2%) leading to discontinuation of intravenous amiodarone therapy are hypotension, asystole/cardiac arrest/pulseless electrical activity, VT, and cardiogenic shock. Other important adverse reactions are, torsade de pointes (TdP), congestive heart failure, and liver function test abnormalities. Fluoroquinolones, macrolide antibiotics, and azoles are known to cause QTc prolongation. There have been reports of QTc prolongation, with or without TdP, in patients taking amiodarone when fluoroquinolones, macrolide antibiotics, or azoles were administered concomitantly. Since amiodarone is a substrate for CYP3A and CYP2C8, drugs/substances that inhibit these isoenzymes may decrease the metabolism and increase serum concentration of amiodarone.