Safety pharmacologyCriticised but acceptedBeyond the letter
In vitro hERG assay deviated from ICH S7B Q&A best practices (voltage protocol, no concentration verification or positive controls)
Why: Additional CiPA-based ion channel studies submitted during review showed no proarrhythmic channel interactions · Weight of evidence
“Although the safety margin of vericiguat on hERG current is high (546-fold), the hERG assay deviates significantly from the new ICH S7B Q&A best practices. Specifically, the study used a different voltage protocol, lacked concentration verification and positive controls”
✓ VerifiedFDA integrated review, p. 146Source ↗ “The applicant submitted the results of these studies on November 18, 2020. Overall, these channel studies also showed no evidence of membrane channel interactions with vericiguat exposure that would result in proarrhythmia.”
✓ VerifiedFDA integrated review, p. 68Source ↗ Impurity or metaboliteAcceptedBeyond the letter
Major human metabolite M1 (70% of human plasma exposure) below 0.24x human AUC in rodent carcinogenicity studies; not separately dosed
Why: Administered M1 unlikely to remain intact through the stomach, so dosing it would add little · Pharmacology or kinetics
“This is an N-glucuronide that accounts for 70% of human plasma exposure and in rat and mouse accounts for less than 10% of total exposure, reaching <0.24X the human AUC.”
✓ VerifiedFDA integrated review, p. 162Source ↗ “The Executive CAC determined that if the M1 metabolite was synthesized and administered, it was not likely to remain intact during passage through the stomach. Therefore, additional synthesis and administration of the compound was not likely to add to the informative value of the studies.”
✓ VerifiedFDA integrated review, p. 162Source ↗ Juvenile toxAccepted with a conditionBeyond the letter
Juvenile rat developmental toxicity study (bone effects) deferred to a postmarketing requirement
Why: Bone effects not expected in the adult heart failure population · Human data
“A non-clinical PMR will be issued to evaluate developmental toxicity in juvenile rats in order to support dosing for potential studies in a pediatric population.”
✓ VerifiedFDA integrated review, p. 86Source ↗ “Conclusion: Bone effects were not observed in VICTORIA and were not expected given the age of the patient population.”
✓ VerifiedFDA integrated review, p. 86Source ↗