Cancer Treatment R&D: Graphene-based Photothermal Therapy

The latest advancements, and perhaps those with the most significance, are finding a role in the field of medicine, including in drug delivery, biological sensing and imaging, antibacterial materials, and tissue engineering. In Europe, where the EU is funding a 10-year, 1.35 billion euro coordination action on graphene, the European Medicines Agency (EMA) has already advanced and written regulations for the use of nanomaterials including graphene-based products. Likewise, the FDA is drafting regulations supporting the development of nanomaterials.

Calevia Inc., a private biotechnology company formed in partnership with ProScanRxPharma Inc. and Grafoid Inc, is now working to develop an innovative graphene-based photothermal therapeutic platform for various cancers. Calevia’s goal is to develop a treatment that targets tumor cells at the molecular level offering better therapeutic efficacy and improved safety over traditional cancer treatments including surgery, radiation therapy and pharmacology.

Surgery and radiation therapy is indiscriminate when it comes to cancer cells and surrounding healthy cell tissue, which can leave patients with serious quality of life issues. In prostate cancer patients, for example, these issues may include incontinence and impotency in a large proportion of patients undergoing invasive procedures. What’s needed in the cancer treatment space is a less-invasive, well-designed treatment that targets cancer cells only, leaving healthy cells intact thus reducing side effects and allowing patients to retain normal organ function.

Life Science Investing News (LSIN) recently spoke with Dr. Claude Vezeau, President and CEO of Calevia, who provided some insight into what makes graphene well-suited for cancer therapy.

LSIN: Currently, Calevia is in the R&D stage with a prostate cancer-targeted treatment. Can you tell us more about the product you’re developing?

Dr. Claude Vezeau: The tumor-specific and photoactivable bio-conjugate we are developing targets prostate cancer and combines two well-characterized products: ProScan’s prostate cancer antibody ligand (PSC1700) and Grafoid’s functionalized and photoresponsive nanomaterial MesoGraf™Xide, a derivative of the universal standard and most pristine form of graphene, MesoGraf™. Our partner ProScan has developed and licensed to Calevia its humanized monoclonal antibody PSC1700 that is highly selective for PSMA, a protein that is over-expressed at the surface of prostate cancer cells and a recognized tumor marker. We’re attaching this PSMA ligand to, MesoGraf™Xide, supplied by our second partner, Grafoid to create a targeted photoresponsive, injectable bio-conjugate.

LSIN: Why graphene? What about this material makes it ideally suited to treating cancer cells?

CV: Graphene has many commercially important properties, but the one that is of interest to Calevia is its photothermal property. MesoGraf™Xide is a graphene-based nano-material that can absorb near-infrared light (NIL) and transform it into heat instantly. Cells are sensitive to heat, so it doesn’t have to be a very high temperature—10 to 12 degree above normal body temperature. At 42 degrees Celsius, cells become sluggish and above 46 degrees, irreversible cellular damage occurs and they die. Therefore, heat becomes the physical treatment that can kill the cancer cells with precision and efficacy when guided to the cancer area by a selective ligand. And that’s what we’re developing. A molecularly-targeted medical treatment that uses localized temperature elevation for the ablation of tumors.

LSIN: How will this graphene-based photothermal therapy target cancer cells without harming surrounding healthy cells?

CV: Following intravenous injection, the bio-conjugate will distribute throughout the patient’s body. The anti-PSMA antibody (PSC1700) will then bind to the targeted cells and start to accumulate on those cells. The non-bonded bio-conjugate will be eliminated from the body. The PSMA anti-body is a smart bomb that acutely targets the prostate cancer cells. That’s the beauty of a molecular targeted treatment. Once the bio-conjugate has accumulated at the surface of the cancel cells, a harmless and tissue penetrating near-infrared light is applied transcutaneously to the cancer area. The photoreactive MesoGraf™Xide will then absorb and transform the NIL into heat, killing the PSMA-expressing cancer cells while sparing surrounding healthy tissues— a clear advantage over other forms of therapy. Our goal is to provide the patient with a non-invasive, out-patient clinical option that is efficient, and has low-side effects and preserves physiological functions.

LSIN: What’s the market for prostate cancer treatment?

CV: Prostate cancer is the most common localized cancer in men with 200,000 new cases each year in the United States. It’s a huge market in need of significant clinical improvement. Industry research projects the prostate cancer market to be about $50 billion by 2017.

LSIN: Any competition currently in this space?

CV: We haven’t seen any graphene-based photothermal treatments in significant advanced stage of development. There is thermal therapy for cancer using ultrasound, or microwave irradiation, but the technology is not selective and is highly dependent on the operator’s skills and accurate mapping of the cancer area to spare healthy tissue. If our non-invasive graphene photothermal treatment proves effective, no man would choose surgery over a targeted treatment that leaves healthy cells unaffected. Additionally, with this treatment we should be able to reach those local microscopic cancer spreads and hopefully lower relapse rates, which now stand at about 30 percent using traditional treatments. We offer the alternative to the traditional surgery, radiotherapy and hormonal therapy early on in the disease.

LSIN: What other types of cancer would you be targeting down the line?

CV: Calevia aims to develop a suit of MesoGraf™Xide bio-conjugates targeting early-stage localized tumors associated with various diseases including urological cancers such as kidney and bladder, those associated with the head and neck as well as breast cancer and skin. As long as we have a tumor specific ligand we can combine it with MesoGraf™Xide to create a cancer-specific photothermal bio-conjugate.

 LSIN: What are Calevia’s goals for the next 2 years?

CV: We have three goals for the next 2 years. The first is to further develop our MesoGraf™Xide platform to accept various cancer selective ligands, with very small modifications, in order to target other cancers. The second goal is to create a first bio-conjugate product for prostate cancer using the highly validated and humanized PSC1700 and MesoGraf™Xide. Both the PSMA antibody and the MesoGraf™Xide material are very well characterized and we have begun working the chemistry to create the bio-conjugate. The third goal is to test the prostate-specific bio-conjugate in cellular and prostate cancer animal models, including mouse xenograft and a translational dog model.

LSIN: When do you expect to initiate human clinical trials?

CV: That’s about two years out. We’ve already started to talk to some investigators, and urologists are keenly interested in our approach as they see huge benefit for patients. One thing that is interesting, the EMA has already advanced and written their regulations for carbon-based nanomaterials. So we know their regulations and we know investigators that are ready to work with our product to bring it to first-in-human and proof of concept in human trials.

LSIN: How will you finance the next two years of study?

CV: We’ve just completing our first round of financing that will be used to support the next two years of research. We’re presenting at the Rodman & Renshaw Global Investment Conference September 9^th, the first big presentation for Calevia. Although Calevia is a new company, it’s not a start-up. We have a well-characterized, humanized antibody which we have a license to and the MesoGraf™Xide is well-developed as well. We’re now working to create the bio-conjugate which is quite simple chemistry. Our partner Grafoid is well-known in the market, busy developing all types of applications for graphene and is able to produce at a large scale and at low cost. They are a valuable partner for us from a development and financing perspectives. They have already opened many doors for us.

LSIN: Thank you for your time, Claude. Wonderful speaking with you.

CV: You as well. Thank You.

Securities Disclosure: I, Melissa Pistilli, hold no direct investment interest in any company mentioned in this article.