The Promise of Nuclear Medicine: Developing Cancer Detection and Treatment with Molecularly Targeted Radiation (MTR)
Nuclear medicine has long suffered from a dearth of innovative, late-stage products that both, detect and improve the treatment of cancer. That’s why Chris Behrenbruch, co-founder and CEO of Telix Pharmaceuticals, is committed to delivering on the promise of nuclear medicine to help cancer patients live longer, and with a better quality of life. The company’s goal is to become a global leader in the development and distribution of disruptive precision oncology products by 2021.
“On both the imaging and the therapy side, nuclear medicine helps support smarter decisions and quality of life. When you're treating patients with advanced metastatic disease, you're not only giving them a potential survival benefit, you're also reducing pain and enabling them to have a more active life,” says Behrenbruch.
Decades of Experience
Behrenbruch founded the Australia-based company in 2015 with Andreas Kluge, a well-known nuclear medicine drug developer. Through decades of experience, Behrenbruch and Kluge have seen the evolution and growth of radiopharmaceutical approaches to diagnostics and therapeutics, along with the development of new supply chains for isotopes such as Lutetium-177, Actinium-225 and Gallium-68.
“With the clinical data and supply chain behind us, we can turn the fantastic work from academia into a commercial platform. Telix's mission is to build on the shoulders of that great research to develop products for academia and cancer centers around the world doing ‘theranostic’ nuclear medicine, while making sure our products have widespread utility,” says Behrenbruch.
Molecularly targeted radiation for personalized therapy
Telix is focusing in particular on molecularly targeted radiation (MTR). In MTR therapy, a radionuclide is attached to a targeting agent such as a small molecule or antibody. This agent specifically binds to and delivers a radioactive payload to tumor cells. This payload can serve either diagnostically (through imaging), therapeutically, or both. MTR offers the potential for better-informed treatment decisions and personalized therapy, which can lead to better outcomes.
Telix delivers investigational products to 60 countries through a network of partners and is running clinical trials in 25 countries. Telix’s current pipeline is concentrated on the development and commercialization of several clinical-stage agents for prostate, renal, and glioblastoma cancers. The company is also actively exploring opportunities for expansion of diagnostic and therapeutic approaches to other important clinical applications.
“These cancers represent a high unmet medical need, with lots of potential for targeted radiation strategy. But we certainly see the potential for this technology in the full continuum of cancer care,” says Behrenbruch.
Exciting applications in prostate cancer
Prostate cancer is the fourth-most common cancer worldwide, with 1.3 million cases and 365,000 deaths in 2018. In the United States, clinicians conduct about 100,000 prostatectomies a year, with 50,000 to 60,000 biochemical recurrences of this cancer. In those biochemical recurrences, prostate-specific membrane antigen (PSMA) imaging could help post-prostatectomy patients with rising PSA levels. “If you can find the site of a local or regional recurrence, you can offer dramatic new intervention options to see better outcomes,” Behrenbruch says.
PSMA is a tumor-associated antigen and type II transmembrane protein, expressed on the membrane of prostatic epithelial cells and over-expressed on prostate tumor cells. 68Ga-PSMA-11 is a radioisotope that, upon intravenous administration, targets and binds to PSMA-expressing tumor cells. PSMA-expressing tumor cells can then be detected during positron emission tomography (PET) imaging. imaging.
Telix is collaborating with academic and commercial institutions to optimize radiation therapy with PSMA imaging, which can also be used to help high-risk men undergoing prostatectomy. “Recently published data shows that if we get in early and we image and stage those patients correctly, it could have a big impact on patients with prostate cancer,” says Behrenbruch.
“This field has a ton of momentum. Although it [the PSMA imaging kit] is not yet FDA approved, it's great to see that, in the practice guidelines in Europe and the United States, that PSMA imaging is already recognized as a necessary standard of care,” he says.
Fast, easy kit preparation for prostate imaging
Telix’s investigational prostate cancer program consists of a companion diagnostic imaging agent (TLX591-CDx) and a therapeutic (TLX591), which are designed to improve metastatic prostate cancer detection and treatment.
The diagnostic agent comes in a “cold kit” for rapid preparation of 68Ga-PSMA-11 for injection and is compatible with major commercially available 68Ga generators. The kit---one of the first under development---enables users to access PSMA-11 as needed, to prepare the 68Ga-PSMA-11 dose proximal to patient imaging within a few minutes.
“You can literally make your dose on the fly. That means we can equip a large number of hospitals and nuclear pharmacies to readily make this product available,” Behrenbruch says.
Clinical trials underway
The TLX591 CDx cold kit is currently under evaluation or being used in over 30 research studies across the US including Emory University Hospital, Memorial Sloan Kettering Cancer Center, City of Hope, and Endocyte [Novartis], under US Investigational New Drug applications, as well as in Canada under the Special Access Program. In clinical trials such as the VISION trial, it is hoped that through an established standard of care PSMA imaging can impact prostate cancer diagnosis, treatment, and improved outcomes.
Telix has established a network of US partners, including approximately 100 nuclear pharmacies, to prepare and distribute the kits for investigational use in qualified, sponsored clinical trials. Noting that the product is available through several distributors around the globe, Behrenbruch stated, “Now there isn't a corner of America, Europe, or any country we serve that won’t be able to offer prostate imaging to their patients. It doesn’t matter if it's a New York-area hospital or a hospital in a remote area, everybody's going to have access to this technology.”
Moving forward amid COVID-19
Despite the COVID-19 pandemic, Telix continues to support its cancer care partners. “Cancer doesn't stop for a pandemic. Last year, we delivered around 12,000 doses of our investigational products worldwide, and I expect that trend will continue,” says Behrenbruch.
In July, Telix participated in The Society of Nuclear Medicine & Molecular Imaging (SNMMI) 2020 Annual Meeting-Virtual Edition; the company hosted a virtual booth where participants learned about its product pipeline and interacted with their staff in real-time chat.
Telix also sponsored a symposium, “PSMA Imaging, Current Status and Prospects and its Clinical Applications,” which highlighted next-generation imaging with PSMA-PET and featured globally recognized panelists from nuclear medicine, urology, and oncology.
“This was a very exciting symposium, and it provided a lot of intellectual and clinical value for the attendees. They received the benefit of hearing from the investigators and clinicians on the front line demonstrating the utility of this,” says Behrenbruch.
“We see such potential benefit to patients, across many disease areas. And if we can build reliable, highly usable, accessible technologies that are easy to use and cost effective, this field is going to become a mainstream part of cancer care. And that's an exciting place to be,” he concluded. Look for more from Telix Pharmaceuticals, including the opportunity to visit with the company and its representatives at the virtual RSNA 2020 meeting.
Editor’s Note: Applied Radiology spoke with Christian Behrenbruch, Chief Executive Officer of Telix Pharmaceuticals, about the company’s growth and focus on helping patients with cancer live longer and better lives. This article is based on that conversation.
*No Telix agent has received regulatory authorization in any jurisdiction.