Atazanavir and Lorlatinib interaction
Atazanavir and Lorlatinib: both prescribing labels flag this combination with the strongest language, such as a contraindication, a boxed warning, or an instruction to avoid it.
Do not combine without a prescriber's guidance. The label language below is the strongest FDA uses.
What the FDA labels say
From the Atazanavir (REYATAZ) label · effective 2024-12-05
• when coadministered with drugs that are strong inducers of CYP3A due to the potential for loss of therapeutic effect and development of resistance.
• Coadministration with drugs that are strong inducers of CYP3A, due to the potential for loss of therapeutic effect and development of resistance.
Initiation of medications that inhibit or induce CYP3A may increase or decrease concentrations of REYATAZ with ritonavir, respectively.
Potential for Other Drugs to Affect REYATAZ Atazanavir is a CYP3A4 substrate; therefore, drugs that induce CYP3A4 may decrease atazanavir plasma concentrations and reduce REYATAZ’s therapeutic effect ( see Table 16 ).
Corticosteroids: dexamethasone and other corticosteroids (all routes of administration) ↓ atazanavir ↑ corticosteroids Coadministration with dexamethasone or other corticosteroids that induce CYP3A may result in loss of therapeutic effect of REYATAZ and development of resistance to atazanavir and/or ritonavir.
From the Lorlatinib (Lorbrena) label · effective 2026-06-26
• Strong CYP3A Inhibitors : Avoid concomitant use; reduce LORBRENA dose if concomitant use cannot be avoided.
Strong CYP3A Inhibitors Avoid concomitant use of LORBRENA with a strong CYP3A inhibitor.
Concomitant use with a strong CYP3A inhibitor increased lorlatinib plasma concentrations [see Clinical Pharmacology (12.3) ] , which may increase the incidence and severity of adverse reactions of LORBRENA.
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Open in the checkerNot medical advice. Interaction Checker quotes FDA label text and NIH fact sheets. Whether an interaction matters for you depends on doses, timing, kidney and liver function, and other conditions. Confirm with a pharmacist or prescriber.