Melbourne – 27September 2022. First Patient Enrolled in ProstACT TARGET Study
Telix and GenesisCare, the largest provider of integrated cancer care in Australia, today announce that a first patient has been enrolled in the Phase II ProstACT TARGET study of Telix’s prostate cancer antibody therapy candidate TLX591 (177Lu-DOTA-rosopatamab), in patients experiencing a first recurrence of prostate-specific antigen (PSA) after initial therapy for prostate cancer.
Telix’s ProstACT therapeutic program is evaluating the efficacy of the Company’s prostate-specific membrane antigen- (PSMA-) targeting lutetium-177 (177Lu)-labelled therapeutic antibody, TLX591, in various stages of prostate cancer, from first recurrence to advanced metastatic disease. The primary focus of the ProstACT series of studies is to complete the pivotal Phase III ProstACT GLOBAL study in a second-line setting in patients with metastatic castration-resistant prostate cancer (mCRPC) progressing on first-line novel androgen agents.
The TARGET study, a collaboration between Telix and research partner, GenesisCare, is exploring the potential of TLX591 in combination with external radiation in patients at an earlier stage in their prostate cancer, providing direction for future indication expansion. The study, which targets enrolment of 50 patients across multiple Australian sites, enrolled the first patient at GenesisCare’s integrated cancer centre at the St John of God Hospital Murdoch campus in Western Australia. The clinical trial is being run through GenesisCare’s global Contract Research Organisation and its Australian network of dedicated theranostics centres.
The third concurrent study in the ProstACT program, ProstACT SELECT, is a theranostic (imaging and therapy) Phase I radiogenomics study to demonstrate the utility of Telix’s imaging agent Illuccix® (kit for the preparation of gallium-68 (68Ga) Glu-urea-Lys(ahx)-hbed-CC, also known as 68Ga-PSMA-11 injection) to select patients for TLX591 therapy given as two doses 14 days apart.
Principal Investigator for the ProstACT TARGET study and GenesisCare Group Medical Director (Theranostics), Professor Nat Lenzo said, “I’m excited to commence this important study that builds on the momentum of ProstACT SELECT. With previous studies having confirmed the preliminary efficacy and safety profile of TLX591, GenesisCare is pleased to partner with Telix to further their therapeutic antibody-based program, which has potential to improve health outcomes for thousands of men living with prostate cancer in Australia and worldwide.”
Telix Chief Medical Officer Dr. Colin Hayward added, “Enrolling a first patient in the ProstACT TARGET study is a significant milestone in Telix’s overall clinical mission to support men with prostate cancer at every step in their journey with a PSMA antibody approach to targeted radiation therapy. Alongside ProstACT SELECT, this program will add value and clinical insight to Telix’s antibody therapy candidate TLX591, as we progress global regulatory submissions for the ProstACT GLOBAL Phase III study. We wish to express our gratitude to Professor Nat Lenzo and his clinical team, as well as the patients who will contribute to the study.”
ProstACT is a series of studies of the investigational product TLX591, the Company’s antibody-based, PSMA targeted prostate cancer therapy candidate TLX591 (177Lu-DOTA-rosopatamab).
The three studies running concurrently in the program are:
ProstACT GLOBAL, a Phase III international, multi-centre, randomised controlled trial (RCT) in patients with PSMA-expressing mCRPC, experiencing disease progression following prior treatment with a novel androgen axis drug. The ProstACT trial will enrol up to 390 patients and incorporates patient selection using 68Ga-PSMA imaging with TLX591-CDx (Illuccix). The trial will compare standard of care therapy alone versus standard of care therapy plus TLX591, with a primary endpoint of radiographic progression-free survival (rPFS).
Status: sites in Australia and New Zealand are being prepared to commence patient screening, ahead of initiating global sites.
ProstACT SELECT, a Phase I radiogenomics study with the goal of comparing 68Ga-PSMA (gallium) and 177Lu-PSMA (lutetium), specifically exploring the biodistribution differences between small molecule and antibody-based targeting. The study is designed to inform optimal patient selection for Telix’s antibody-based 177Lu therapy, with the goal of enabling indication expansion for Telix’s PSMA therapeutic portfolio. ProstACT SELECT is a multi-centre study and will enrol up to 50 patients, with a first patient dosed in January 2022.
Status: first cohort of patients dosed.
ProstACT TARGET, a Phase II single arm study in Australia in 50 patients with PSMA-avid biochemically recurrent oligometastatic (five or less metastases) prostate cancer, in combination with external beam radiation therapy (EBRT). The clinical objectives are delaying disease recurrence and thus deferring the commencement of androgen deprivation therapy (ADT) with the primary endpoint biological progression-free survival (PFS BIO). The study is a collaboration with Telix’s strategic partner, GenesisCare. GenesisCare will be enrolling patients at its integrated cancer centres at GenesisCare North Shore, Sydney and GenesisCare at the St John of God Hospital, Murdoch campus, Perth.
Status: patient enrolment has commenced.
 ASX disclosure 27 January 2022.
 Defined by PSMA PET imaging.
To read Telix’s press release please click here