Photodynamic therapy (PDT) with mTHPC in the palliation of advanced head and neck cancer in patients who have failed prior therapies and are unsuitable for radiotherapy, surgery or systemic chemotherapy

Abstract

5596 Background: A previous clinical trial showed that the novel PDT drug, mTHPC, is effective in improving quality of life in patients with advanced head and neck cancer. This current, ongoing, multinational, open-label study is being conducted to confirm that finding. Methods: Patients with advanced squamous cell carcinoma of the head and neck, who have failed prior therapies, and are unsuitable for curative therapy, are being enrolled in this single-arm, palliative care study. Each patient has a tumour that is accessible for unrestricted laser light illumination and is no greater than 10 mm in depth. The primary endpoint of the study is the overall tumour response rate. In addition, quality of life, an important measure in this end-stage population, is being assessed. Patients receive a 0.15-mg/kg intravenous dose of mTHPC followed 96 hours later by illumination of the tumour with a diode laser (light dose 20 J/cm2, irradiance 100 mW/cm2, wavelength 652 nm). Results: To date, 10 patients have been treated in the study. The mean age of patients is 61 years (range, 44 to 82 years). Interim data indicate that 5 patients (50%) have achieved a complete tumour response and 2 patients a partial response (using WHO criteria), thus 7 of 10 patients (70%) have experienced an overall tumour response. The adverse events observed so far in the study are typical of those seen with mTHPC, and include pain, oral necrosis, and trismus. Investigators involved in the study have commented upon the ability of mTHPC to preserve functional and anatomical integrity, which in turn affords patients an improved quality of life. Conclusions: The results, based on these interim data, confirm the effectiveness of mTHPC in reducing tumour mass, and therefore suggest that mTHPC may indeed improve or maintain quality of life. Author Disclosure Employment or Leadership Consultant or Advisory Stock Ownership Honoraria Research Funding Expert Testimony Other Remuneration Biolitec Pharma Biolitec Pharma Biolitec Pharma