Women who use drugs in Tanzania face a disproportionately high burden of HIV and mental health disorders. Despite the availability of pre-exposure prophylaxis (PrEP), uptake remains low, highlighting the need for integrated, scalable interventions that address co-occurring substance use and mental health challenges. Motivational interviewing (MI) and cognitive-behavioural approaches, such as the Common Elements Treatment Approach (CETA), show promise for enhancing HIV prevention outcomes in this population. This study presents the protocol for a pilot feasibility trial assessing the acceptability, feasibility and preliminary efficacy of MI for PrEP (MI-PrEP) and a combined CETA and MI-PrEP intervention (CETA + MI-PrEP) to improve PrEP engagement among women who use drugs in Tanzania.

This individually randomised, parallel-group pilot trial will be conducted in Dar es Salaam, Tanzania, guided by the situated Information, Motivation and Behavioral Skills model. Eligible participants are adult women who use heroin, report recent drug-related or sex-related HIV risk behaviours, are HIV-negative and exhibit symptoms of depression, anxiety or post-traumatic stress disorder. Participants are randomised to one of three arms: MI-PrEP, CETA + MI-PrEP or enhanced treatment as usual. Interventions are delivered face-to-face by trained counsellors. Feasibility and acceptability will be assessed using recruitment and retention data, surveys and qualitative interviews. Preliminary effects will be measured for PrEP initiation, symptoms of common mental disorders and substance use.

Ethical approval has been obtained from the Johns Hopkins Bloomberg School of Public Health Institutional Review Board (25580), the Muhimbili University of Health and Allied Sciences Ethics Review Committee (MUHAS-REC-12-2023-1994) and the National Health Research Ethics Committee at the National Institute for Medical Research in Tanzania (NIMR/HQ/R.8a/Vol.IX/4830). Results will be disseminated through ClinicalTrials.gov, peer-reviewed publications, conferences, presentations and research briefings to community stakeholders.

ClinicalTrials.gov ID: NCT06835751. Initially registered 14 February 2025, https://clinicaltrials.gov/study/NCT06835751, last updated 5 December 2025.

Radioembolisation (RE) is gaining traction as a robust treatment option for patients with hepatocellular cancer (HCC) across all cancer stages. RE allows the delivery of targeted high-dose radiation directly to tumours, with relative sparing of the surrounding liver tissue. Traditionally, radiation has been delivered using ⁹⁰Yttrium ([⁹⁰Y]Y)-labelled microspheres, either glass or resin. The success of RE is dependent on the dose delivered to the tumour. When using [⁹⁰Y]Y microspheres, dose prediction is calculated through a ^99mTechnitium ([^99mTc]Tc)-macroaggregated albumin (MAA) scan, which allows the calculation of the dose to be administered to the tumour. However, [^99mTc]Tc-MAA is not a true surrogate of [⁹⁰Y]Y microspheres, and this will impact on the final dose delivered. [¹⁶⁶Ho]Ho, like [⁹⁰Y]Y, is a beta emitter but unlike [⁹⁰Y]Y also emits gamma-radiation, allowing for quantitative nuclear imaging. The primary aim of this pilot study was to investigate the safety and efficacy of dosimetry-based individualised ¹⁶⁶Holmium ([¹⁶⁶Ho]Ho-RE) in patients with HCC.

15 eligible participants will be recruited to receive [¹⁶⁶Ho]Ho-RE. The primary objective is to establish the toxicity profile of dosimetry-based individualised [¹⁶⁶Ho]Ho-RE. The secondary objective is to assess efficacy as measured by modified Response Evaluation Criteria in Solid Tumours (mRECIST) and Response Evaluation Criteria in Solid Tumours (RECIST) 1.1 criteria. Additional exploratory objectives include quality of life assessment and identification of a radiomic signature of response. The results from this study will be combined with the prospective iHEPAR study to form a larger analysis.

The study has received approval from the East Midlands—Nottingham 1 Research Ethics Committee—approval number 23/EM/0239. The study will be performed in compliance with the Declaration of Helsinki and the principles of Good Clinical Practice. Signed informed consent will be obtained from each patient before study entry. The results will be disseminated through publication in a peer-reviewed scientific journal.

Clinicaltrials.gov NCT06302400.