Reflexion Medical Inc. appears to be on a roll. A little more than a month after unveiling a tie up with Merck & Co. Inc., it now has reported a collaboration with Telix Pharmaceuticals Ltd., a radiopharmaceutical company developing molecularly targeted radiation products.
Specifically, the two will investigate the clinical utility of combining technologies to improve treatment for high-risk or recurrent prostate and aggressive kidney cancers. Of note, they will evaluate several new positron emission tomography (PET) tracers, including 68Ga-PSMA-11 for prostate cancer and 89Zr-Girentuximab for kidney cancer, to evaluate their potential in guiding biology-guided radiotherapy (BgRT) to treat disease.
“The Telix tracers show considerable potential for detecting metastatic disease,” said Phuoc Tran, professor of radiation oncology and molecular radiation sciences, oncology and urology at the Johns Hopkins School of Medicine. “Combining them with Reflexion’s BgRT, which is designed to treat metastatic disease, could bring us a step closer to improving outcomes for these cancer types.”
BgRT relies on biological emissions from a patient’s cancer cells created by injecting a small amount of a targeting molecule carrying a PET tracer to guide external-beam radiotherapy. As the PET tracer binds to the tumor cells, it produces emissions signaling the cancer’s location. The Reflexion X1 machine detects these emissions using PET detectors and directs BgRT to each tumor and destroy it, even in those that are moving.
The Reflexion X1 machine with BgRT is not available for sale but is designed to overcome the technical limitations that restrict radiotherapy delivery to one or two sites of disease. It instead allows such therapy to reach multiple areas during the same treatment session.
Earlier this year, the company announced that the U.S. FDA had allowed it to market its Reflexion X1 system for standard radiation therapy treatments. Specifically, the agency cleared the system for stereotactic body radiotherapy, stereotactic radiosurgery and intensity modulated radiotherapy.
The most commonly used PET tracer is 18F-fluorodeoxyglucose (FDG), which can detect a host of cancer types. However, its performance in certain tumor types and organs remains limited – particularly for kidney and prostate cancers. Telix’s new PET tracers aim to target specific cancer types and are expected to be more accurate in the clinical setting.
Thorsten Melcher, chief business officer at Hayward, Calif.-based Reflexion, told BioWorld that the company is excited to work with Telix. He noted that Melbourne, Australia-based Telix has developed a portfolio of PET tracers in cancer types that are of great interest to his company. Further, Telix has the ability to push these tracers through clinical development.
“These novel tracers may be superior to FDG in detecting metastatic disease of the prostate and the kidney ... and in guiding Reflexion’s BgRT,” he explained. “Further, as one of the few companies fully committed to a theranostics approach to detect and treat cancer, Telix is developing therapeutic radiopharmaceuticals that may be used in combination with Reflexion’s BgRT in the future – combining a Telix drug targeting micrometastatic disease with Reflexion’s device-based BgRT to target bulky disease in a metastatic patient.”
He further noted that both interventions depend on radiation as the therapeutic modality.
“Using Telix’ novel PET tracers, Reflexion’s BgRT would be guided in a cancer-specific manner to sites of disease, thereby enabling treatments in situations where current technology is suboptimal,” he explained. “Such Telix PET tracer-guided BgRT would be more precise and thus sparing normal tissue.”
As a result, patients would experience better outcomes in terms of safety and efficacy. "Further, as external-beam radiotherapy techniques such as BgRT have been demonstrated to be extremely cost-efficient, in particular when compared to novel pharmaceutical approaches such as immunotherapy or cell/gene-based therapies, we may expect a reduction in overall treatment costs for certain patient populations.”
Reflexion’s collaboration with Merck is evaluating the safety and efficacy of Keytruda (pembrolizumab) in combination with BgRT in multiple late-stage cancers.
The goal is to establish whether treating multiple tumors with BgRT, a novel external beam radiotherapy treatment modality in development, is safe and amplifies Keytruda’s therapeutic effect.
“There are no announcements in the next coming weeks, however, we continue to engage in ongoing discussions with multiple parties to further build our external innovation ecosystem,” Melcher told BioWorld when asked if more partnerships could be announced in the coming weeks. “We may have an announcement later this year.”