Pre-exposure prophylaxis (PrEP) with antiretroviral (ARV) drugs are effective at preventing human immunodeficiency virus (HIV) transmission. However, implementation of PrEP presents significant challenges due to poor user adherence, low accessibility to ARVs and multiple routes of HIV exposure. To address these challenges, we developed the nanochannel delivery implant (NDI), a subcutaneously implantable device for sustained and constant delivery of tenofovir alafenamide (TAF) and emtricitabine (FTC) for HIV PrEP. Unlike existing drug delivery platforms with finite depots, the NDI incorporates ports allowing for transcutaneous refilling upon drug exhaustion. NDI-mediated drug delivery in rhesus macaques resulted in sustained release of both TAF and FTC for 83 days, as indicated by concentrations of TAF, FTC and their respectively metabolites in plasma, PBMCs, rectal mononuclear cells and tissues associated with HIV transmission. Notably, clinically relevant preventative levels of tenofovir diphosphate were achieved as early as 3 days after NDI implantation. We also demonstrated the feasibility of transcutaneous drug refilling to extend the duration of PrEP drug delivery in NHPs. Overall, the NDI represents an innovative strategy for long-term HIV PrEP administration in both developed and developing countries.
Mounting evidence demonstrates that combining radiation therapy (RT) with immunotherapy can reduce tumor burden in a subset of patients. However, conventional systemic delivery of immunotherapeutics is often associated with significant adverse effects, which force treatment cessation. The aim of this study was to investigate a minimally invasive
Tumor uptake and biodistribution of immunotherapy is associated with clinical response as well as toxicity. To augment immunotherapy bioavailability in the tumor, an intratumoral administration route via direct injection or local release technologies has emerged as an appealing approach. Here the biodistribution of an agonistic anti-CD40 monocolonal antibody (CD40 mAb) when sustainably delivered via an intratumoral nanofluidic drug-eluting seed (NDES) is evaluated in comparison to systemic or direct intratumoral administration. The NDES achieves sustained drug release through diffusion by leveraging electrostatic nanoconfinement within nanochannels, without requiring internal or external actuation. Using the 4T1 murine mammary carcinoma model, the biodistribution of Alexa Fluor-700 conjugated CD40 mAb is tracked via fluorescence imaging analysis, comparing three routes of administration over 7 and 14 days. NDES-treated cohort shows sustained high levels of intratumoral CD40 mAb without off-target organ exposure, compared to the intraperitoneal and direct intratumoral administration. Moreover, radiation pre-treatment of the 4T1 tumors augments tumor retention of CD40 mAb in the NDES group. Overall, sustained intratumoral release of CD40 mAb via the NDES improves local drug bioavailability without systemic dissemination, suggesting an enhanced approach for immunotherapy administration.
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