Sunstone Therapies Announces Start of First Study of Multiple Doses of Psilocybin in Treatment of Depression in Patients with Cancer

Sunstone Therapies Announces Start of First Study of Multiple Doses of Psilocybin in Treatment of Depression in Patients with Cancer

Phase 2 study to examine safety and efficacy of up to two doses of psilocybin in cancer patients with major depressive disorder

Rockville, Maryland, November 06, 2023 – Sunstone Therapies, a leader in the delivery of psychedelic-assisted therapy in the medical setting and the development of clinical trials, announces today that the first patients in its phase 2 multiple-dose psilocybin study have received treatment. Study participants are adults with cancer and major depressive disorder (MDD) who are receiving up to two doses of psilocybin with concurrent therapy.

Sunstone aims to recruit 56 patients into this single-center study to explore the efficacy, safety, and tolerability of up to two 25-mg doses of psilocybin administered at an interval of 9 to 10 weeks ( ID NCT05947383).

The two-part study will administer a first dose of psilocybin in a double-blind, randomized, placebo-controlled portion (Dosing Session 1) and subsequently allow rollover into an open-label portion (Dosing Session 2) for patients who did not achieve remission of MDD symptoms after the first dose.

In Dosing Session 1, groups of two to four patients will be randomized, as a cohort, to receive either psilocybin 25 mg or niacin 100 mg (active placebo) in a group session. Each patient is supported by their dedicated study therapist in addition to a second therapist monitoring via video feed. In Dosing Session 2, all eligible participants will receive psilocybin 25 mg in an open-label fashion using the group session model. The study population will include individuals 18 years of age or older who have diagnoses of both MDD and a malignant neoplasm.

The primary efficacy endpoint (psilocybin versus active placebo) will be the change in the Montgomery-Asberg Depression Rating Scale (MADRS) from baseline to week 8. Additional secondary endpoints will be used to assess a range of parameters in both the placebo-controlled and open label study conditions. Secondary endpoints will include the onset and durability of response, response rate and remission, and the effect on pain.

The trial will be conducted at the Bill Richards Center for Healing at the Aquilino Cancer Center which has been designed for the delivery of psychedelic-assisted therapies in a setting that is patient-centric, responsible, safe and effective.

Paul Thambi MD, Chief Medical Officer at Sunstone Therapies, and Principal Investigator on the study, commented: “The emotional distress associated with cancer is often as significant as the physical effects, and yet oncologists have few effective treatments to tackle this important aspect of the patient experience. More recently, the use of psychedelic-assisted therapy has seen renewed interest and a number of studies show a positive impact on symptoms of depression in patients with cancer, including our own open label study published in JAMA Oncology. This new study includes a placebo control arm, the use of group administration, and - for the first time - multiple doses. We believe this adds significantly to the understanding of the role psilocybin-assisted therapy could play in improving patients’ lives and how it might best be delivered.”

Manish Agrawal MD, Chief Executive Officer at Sunstone Therapies, and Clinical Investigator on the study, commented: The Sunstone team has a longstanding commitment to advancing clinical research in psychedelic-assisted therapy in cancer patients, and unique depth of experience across psychedelic modalities and indications. This study builds on our pioneering approach to clinical trial design: there is limited data addressing the question of whether multiple administrations of treatment doses of psilocybin in patients with cancer lead to improved efficacy. We look forward to making a further contribution to the clinical development of this potentially vitally important treatment modality.”


About Sunstone Therapies

Sunstone Therapies is a leader in the delivery of psychedelic-assisted therapy in the medical setting, focusing on clinical trials today and future clinical delivery when therapies are approved. Sunstone is establishing the gold standard for psychedelic clinics in order to deliver care that reduces the emotional suffering of those affected by cancer and complex mental health challenges and disorders, and to make safe, effective psychedelic-assisted therapy accessible.

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