Australian biotech company Starpharma announces positive interim results from the prostate cancer cohort in its ongoing phase 2 trial of DEP® cabazitaxel

Starpharma showed that 100% of evaluable patients with Stage IV prostate cancer have had efficacy responses, utilising one or more standard measures of disease.

DEP® cabazitaxel is a patented, detergent (polysorbate-80[1])-free, nanoparticle version of the conventional cancer drug, Jevtana® - a leading oncology agent used to treat advanced prostate cancer. Sales of Jevtana® exceeded US$600 million in 2020.

Starpharma's interim results in Stage IV prostate cancer show that one or more efficacy signals[2] were observed in 100% of patients assessed following DEP® cabazitaxel treatment.

64% of patients with assessable tumours saw prolonged stable disease and significant reductions in tumour size for up to 36 weeks

90% of patients with assessable PSA (Prostate Specific Antigen) tumour biomarker levels had a PSA reduction; >50% of these patients achieved a PSA reduction of at least 50%

83% of patients with secondary bone disease exhibited either no progression or an improvement in bone disease

56% of evaluable patients had responses to all three measures evaluated

Starpharma's positive interim results are particularly significant given all patients in this cohort had late-stage prostate cancer and had failed multiple anti-cancer treatments, in addition to surgeries and radiation, prior to entering the DEP® cabazitaxel trial.

Importantly, patients treated with DEP® cabazitaxel also experienced less severe bone marrow toxicity, significantly lower rates of severe neutropenia and no instances of neutropenic sepsis, which are associated with conventional cabazitaxel. The absence of detergent-like polysorbate-80 in the DEP® cabazitaxel formulation eliminated the need for prophylactic corticosteroids and antihistamines, with no anaphylaxis or severe hypersensitivity reactions observed. This avoidance of long-term steroid use is attractive, particularly in prostate cancer patients where bone health can be a significant issue.

DEP® cabazitaxel is one of Starpharma's three internal clinical-stage DEP® assets, alongside DEP® docetaxel and DEP® irinotecan, which Starpharma intends to licence following phase 2. Starpharma also has a number of partnered DEP® programs including with AstraZeneca and Merck & Co., Inc.

[1] Polysorbate 80 is a detergent-like substance, which is used to solubilise insoluble molecules, and which is a component of conventional cabazitaxel products, including Jevtana® and generic forms.

[2] Efficacy in the prostate cancer cohort in the trial was assessed referencing the applicable aspects of the internationally recognised Prostate Cancer Working Group (PCWG3) guidelines.

Source: Starpharma