Abstract
Non-muscle invasive bladder cancer (NMIBC) accounts for the majority of newly diagnosed bladder cancer (BC) cases and is known for its high recurrence rate after initial treatment. The current standard of care includes the transurethral resection of bladder tumor (TURBT), followed by adjuvant intravesical therapy. However, therapeutic outcomes of intravesical therapies are often limited by the physiological characteristics of the urinary bladder, including continuous urine production and voiding, as well as the presence of the bladder permeability barrier (BPB), which reduces drug retention time and limits therapeutic efficacy. In response to these limitations, nanoparticle-based (NP-based) drug delivery systems (DDS) have emerged as a promising tool to prolong intravesical drug retention, improve treatment efficacy, and minimize systemic toxicity. This narrative review provides an overview of the available literature on NP-based DDS, with applications in the intravesical treatment of NMIBC, categorizing them into organic, inorganic, carbon-based, and composite-based nanoparticles (NPs). A comprehensive literature search was conducted using PubMed and Google Scholar (up to 2025), with Boolean combinations of terms related to NMIBC, NP-based DDS, intravesical therapy, and the various subtypes of NPs investigated in this review. Each NP subtype offers distinct advantages, such as improved mucoadhesion, controlled drug release, multifunctionality, and potential for targeted delivery. Preclinical studies have shown encouraging outcomes; however, there is a lack of clinical data due to concerns related to toxicity, cost, scalability, and regulatory approval. Continued research and well-designed clinical trials are crucial for validating the safety and efficacy of NP-based DDS. In the future, the successful integration of NP-based DDS into intravesical therapy of NMIBC could reduce recurrence rates and improve therapeutic outcomes.