P1106 is Phase IV prospective pharmacokinetic (PK) study of low birth weight infants who are receiving or will be receiving as part of clinical care nevirapine (NVP) prophylaxis, tuberculosis (TB) prophylaxis or treatment and/or combination antiretroviral (ARV) treatment containing lopinavir/ritonavir (LPV/r). The study is designed to describe the pharmacokinetics and safety of NVP, INH, RIF, and LPV/r in these infants receiving the drug(s) as part of clinical care.

Inclusion Criteria:

Inclusion Criteria for Arms 1 and 3 (HIV-exposed infants):

• Breastfeeding infants born to HIV-infected mothers who are receiving either no ARV therapy or ARV therapy that does not include NVP
• Age 7 to 14 days
• Birth weight less than 2500 grams
• Receiving or will be receiving prophylaxis as prescribed by clinical care provider as follows: NVP (Arm 1), NVP plus INH (Arm 2), NVP plus INH plus RIF (Arm 3)
• Parent or legal guardian able and willing to provide written informed consent. [Note to sites: modify per locally relevant language].

Inclusion Criteria for Arm 2 (HIV-exposed infants):

• Breastfeeding infants born to HIV-infected mothers who are receiving either no ARV therapy or ARV therapy that does not include NVP
• Age 7 to 84 days
• Birth weight less than or equal to 4000 grams
• Receiving or will be receiving prophylaxis as prescribed by clinical care provider as follows: NVP (Arm 1), NVP plus INH (Arm 2), NVP plus INH plus RIF (Arm 3)
• Parent or legal guardian able and willing to provide written informed consent. [Note to sites: modify per locally relevant language].

Inclusion Criteria for Arm 4 (HIV-unexposed but TB exposed infants):

• Age 7 to 84 days
• Birth weight less than or equal to 4000 grams
• Receiving prophylaxis with INH alone or INH plus RIF as prescribed by clinical care provider
• Not receiving any therapy for HIV prophylaxis or treatment
• Parent or legal guardian able and willing to provide written informed consent. [Note to sites: modify per locally relevant language].

Inclusion Criteria for Arms 5 and 6 (HIV-infected infants):

• Documentation of HIV-1 infection defined as positive HIV DNA PCR done as part of clinical care. An HIV RNA confirmatory test must be done at study entry but results may be pending at time of enrollment.
• Birth weight less than or equal to 4000 grams
• Age less than or equal to 12 weeks (defined as 84 days)
• Intention by clinical care provider to prescribe LPV/r plus 2 NRTIs and no RIF (Arm 5) or LPV/r plus 2 NRTIs plus RIF (Arm 6)
• Parent or legally acceptable representative able and willing to provide written informed consent. [Note to sites: modify per locally relevant language].

Exclusion Criteria:

Any severe congenital malformation or other medical condition incompatible with life or that would interfere with study participation or interpretation, as judged by the examining clinician.

Low birth weight (LBW) infants less than or equal to 2500 grams at birth who are receiving or will be receiving as part of clinical care nevirapine (NVP) prophylaxis, tuberculosis (TB) prophylaxis or treatment and/or combination antiretroviral (ARV) treatment containing lopinavir/ritonavir (LPV/r)

Individual participant data that underlie results in the publication, after deidentification.

Beginning 3 months following publication and available throughout period of funding of the International Maternal Pediatric Adolescent AIDS Clinical Trial (IMPAACT) Network by NIH.

• With whom? Researchers who provide a methodologically sound proposal for use of the data that is approved by the IMPAACT Network.
• For what types of analyses? To achieve aims in the proposal approved by the IMPAACT Network.
• By what mechanism will data be made available? Researchers may submit a request for access to data using the IMPAACT "Data Request" form at: https://www.impaactnetwork.org/studies/submit-research-proposal. Researchers of approved proposals will need to sign an IMPAACT Data Use Agreement before receiving the data.