Advances in the development of intralesional therapies for melanoma

A Novel In Situ Dendritic Cell Vaccine Triggered by Rose Bengal Enhances Adaptive Antitumour Immunity

Dendritic cell- (DC-) based vaccination has emerged as a promising antitumour immunotherapy. However, overcoming immune tolerance and immunosuppression in the tumour microenvironment (TME) is still a great challenge. Recent studies have shown that Rose Bengal (RB) can effectively induce immunogenic cell death (ICD) in cancer cells, presenting whole tumour antigens for DC processing and presentation. However, the synergistic antitumour effect of combining intralesional RB with immature DCs (RB-iDCs) remains unclear. In the present study, we investigated whether RB-iDCs have superior antitumour effects compared with either single agent and evaluated the immunological mechanism of RB-iDCs in a murine lung cancer model. The results showed that intralesional RB-iDCs suppressed subcutaneous tumour growth and lung metastasis, which resulted in 100% mouse survival and significantly increased TNF-α production by CD8⁺ T cells. These effects were closely related to the induction of the expression of distinct ICD hallmarks by RB in both bulk cancer cells and cancer stem cells (CSCs), especially calreticulin (CRT), thus enhancing immune effector cell (i.e., CD4⁺, CD8⁺, and memory T cells) infiltration and attenuating the accumulation of immunosuppressive cells (i.e., Tregs, macrophages, and myeloid-derived suppressor cells (MDSCs)) in the TME. This study reveals that the RB-iDC vaccine can synergistically destroy the primary tumour, inhibit distant metastasis, and prevent tumour relapse in a lung cancer mouse model, which provides important preclinical data for the development of a novel combinatorial immunotherapy.

Intralesional Agents in Dermatology: Pros and Cons

Since introduced in 1961, intralesional (IL) agent has become an essential part of the dermatological practice. The term IL referred to the direct delivery of agent percutaneously into skin lesions. This therapeutic approach is relatively safe, easy to perform and applicable for a broad range of dermatological conditions. On the other hand, immediate side effects, including pain during administration, bleeding, high risk of infection and allergic reaction, and subsequent side effects involving skin changes such as atrophy, telangiectasia, pigmentary changes, and striae are usually associated with this modality. This review paper highlights the pros and cons of IL agents in modern dermatology practice.

Real-world use of talimogene laherparepvec in Germany: a retrospective observational study using a prescription database

Aim: There is a growing body of data on real-world use of talimogene laherparepvec (T-VEC). We aimed to characterize real-world T-VEC use using a nationally representative German prescription database covering 60% of prescriptions reimbursed. Patients & methods: A retrospective analysis was conducted using the German IMS^® LRx prescription database, analyzing patients aged ≥18 years with an initial T-VEC prescription at 10⁶ plaque-forming units (PFU)/ml and ≥1 subsequent prescription at 10⁸ PFU/ml. Median time on T-VEC treatment, patient characteristics and patterns of T-VEC use were described. Results: Of 127 patients prescribed T-VEC, 72 patients (57%) met study criteria. About two-thirds of these patients initiated T-VEC in 2017. Median age at T-VEC initiation was 74 years (range: 44 to 91). Most prescriptions (88%) were dispensed from hospitals. At study end, 26 (36%) patients remained on T-VEC; 46 (64%) had ended treatment. Median duration of T-VEC treatment for all patients was 18.7 weeks (95% CI: 15.3-26.9) and was longer among those who initiated treatment in 2017 versus 2016 (26.7 vs 15.6 weeks, respectively). Median volume administered for the first 10⁶ PFU/ml and second 10⁸ PFU/ml was 4 ml; the volume decreased for subsequent administrations (2 ml by the eighth administration and 1 ml by the 16th administration). Conclusion: This real-world prescription database study showed that patients who initiated treatment in 2017 had a treatment duration in clinical practice that corresponded with the European Summary of Product Characteristics guideline of continuing T-VEC for ≥6 months. Additional long-term data linking drug use with clinical outcomes are needed.