The University of Chicago received a $728,006 federal Project Grant (R01CA288235) from the National Cancer Institute (CFDA 93.393 Cancer Cause and Prevention Research) to conduct a 2x2 factorial randomized controlled trial evaluating the use of intensive behavioral counseling, the smoking cessation aid cytisine, and their combined effects on reducing tobacco and alcohol co-use among people with HIV in Nairobi, Kenya. The trial aims to optimize treatment strategies for this prevalent dual substance use disorder, which significantly increases risks of aerodigestive cancers in this population. The project builds on the university's prior tobacco treatment research in Kenya and will assess intervention cost-effectiveness. If successful, the findings could support wider adoption of the affordable cytisine medication and strengthen the case for its use in other low- and middle-income countries with high burdens of tobacco and alcohol co-use.