Anvisa Publishes New Drug Interaction Studies Guideline and Opens Form to Receive Public Contributions

The Brazilian Health Regulatory Agency (Anvisa) has issued Guideline No. 89/2026, which provides recommendations on the planning, conduct, and interpretation of in vitro and clinical drug interaction studies in the development of medicinal products. The guideline incorporates into the Brazilian regulatory framework the principles set out in ICH M12 – Drug Interaction Studies, adopted by the International Council for Harmonisation (ICH) in May 2024.

The purpose of the Guideline is to align Brazilian regulatory practice with international standards and to increase predictability in the assessment of the effects that concomitant use of medicinal products may have on the safety and efficacy of treatments.

The Guideline is non-binding and advisory in nature. Accordingly, its recommendations do not have the force of law, and alternative approaches may be adopted, if they are scientifically justified considering the specific circumstances and remain consistent with applicable regulatory requirements. Departure from the Guideline’s recommendations does not, by itself, constitute a regulatory violation or provide grounds for rejection of a submission, provided that all applicable legal and regulatory requirements are otherwise met.

Scope and Key Recommendations

The Guideline primarily addresses pharmacokinetic drug interactions mediated by metabolic enzymes and transporters. Its recommendations cover:

Although principally intended for small-molecule products, the Guideline also includes specific considerations for biologics, particularly monoclonal antibodies, and antibody-drug conjugates. Pharmacodynamic interactions and certain absorption-related effects, including those associated with food intake or changes in gastric pH, remain outside its scope.

Drug interaction assessments should be conducted progressively throughout product development, considering both the effects of other products on the investigational medicinal product and the effects of the investigational product on concomitant therapies. The resulting data may support dose adjustments, additional patient monitoring, staggered administration schedules, or restrictions on concomitant use.

Why Does This Matter?

Although non-binding, the recommendations contained in the Guideline reflect Anvisa’s view of current best regulatory practice, pursuant to Article 2, item XIV, of Ordinance No. 162/2021.

The Guideline has been effective since 27 October 2026. Its publication also provides for the repeal of Technical Note No. 09/2015/CETER and COPEC/GGMED, which addressed the demonstration of pharmacokinetic interactions in fixed-dose combinations and Clinical Drug Development Dossiers (DDCMs).

Companies involved in the development or registration of medicinal products should assess any potential impact on their development programs, clinical protocols, modelling strategies, and regulatory documentation, particularly where they intend to adopt methodologies that differ from those recommended by the Guideline.

In accordance with the rules governing public participation in the development of regulatory instruments, Anvisa will accept comments on the Guideline until April 26, 2027, through an electronic consultation form.

The Life Sciences & Healthcare team at Souto Correa Advogados remains available to clarify any questions regarding this matter.