A Study of Doravirine/Islatravir in Healthy Lactating Females (MK-8591A-061)

A Clinical Study to Evaluate the Breast Milk and Plasma Pharmacokinetics of MK-8591A in Healthy Lactating Female Participants

The goal of this study is to learn what happens to doravirine (DOR) and islatravir (ISL) in a healthy lactating female's body over time. Researchers want to learn if DOR and ISL are in breast milk.

Inclusion Criteria:

The main inclusion criteria include but are not limited to the following:

• Is at least 6-weeks postpartum at the time of administration of study drug, following the delivery of a healthy singleton neonate
• Is willing and able to express breast milk using an electric pump prior to study drug administration and is expected to be able to express at least 4 times over a 24-hour period after study drug administration

Exclusion Criteria:

The main exclusion criteria include but are not limited to the following:

• Has a history of clinically significant endocrine, gastrointestinal, cardiovascular, hematological, hepatic, immunological, renal, respiratory, genitourinary, psychiatric, or major neurological (including stroke and chronic seizures) abnormalities or diseases
• Has had mastitis within 30 days prior to administration of study drug