Tosk Today

Tosk is a dynamic, privately held biotech founded some 15 years ago by highly respected pharmaceutical veterans who set out to transform cancer treatment. The company is led by CEO Brian Frenzel, who founded four successful medical products companies after serving as director of corporate planning for Syntex Corporation. Headquartered in Mountain View, California, Brian and his team of world class scientists, directors and well known scientific and medical advisory board members have dedicated themselves to improving the quality of life of cancer patients worldwide by stripping painful, life threatening and dose limiting toxic effects from front line cancer therapies. While the media focuses on potentially exciting cancer treatments such as immunotherapies, the reality is, most treatment options date back many decades. They work, but at significant sacrifice in terms of side effects and higher costs.

We achieved a significant milestone in 2018 by earning Proof of Concept for our first drug, TK-90. Human trials involving 25 head and neck cancer patients given the common cancer drug methotrexate along with our drug, TK-90, demonstrated that Tosk's TK-90 was effective in preventing mucositis. Mucositis is the painful, expensive, sometimes fatal side effect often associated with methotrexate as well as other palliative drugs and radiation. Methotrexate is a front line treatment not only for patients with head and neck cancer, but patients suffering from breast, lung, leukemia, non-Hodgkin lymphoma and other cancers. We have initiated a following up test for TK-90 to confirm results of the human trials. We're also close to another important milestone, human trials for our second patented drug TK-39, which blocks the cardiotoxicity that results from a class of widely used cancer drugs known as anthracyclines. These include doxorubicin, daunorubicin, Doxii R and Herceptin R, which are used to treat breast, bladder, and lung cancers as well as lymphoma and leukemia. TK-90 will enter trials within the next few months.

Another recent step forward for the company was earning a $2 million competitive grant from the U. S. Government's National Cancer Institute (NCI) to continue to actively pursue a promising effort to enable treatment for some 40 percent of cancer patients who have a genetic condition that prevents treatment today. The NCI has made this effort one of its highest priorities and enlisted Tosk as an important partner in the initiative.

Tosk's efforts at transforming the very nature of today's standard cancer treatments are based on two proprietary drug discovery platforms that use fruit flies as a tool to efficiently discover new, inexpensive, small molecule drugs. Tosk's broad portfolio of intellectual property and unique product line, unusual for a drug development company our size, makes us an attractive partner for a larger pharmaceutical company looking to broaden or replenish its offerings. Such a partnership should provide our patient investors a favorable financial return. Given the millions of people suffering from cancer globally, the need for Tosk’s revolutionary efforts is obvious, and the market opportunity exceptionally large.

Our Mission

Proven Solutions ImprovedSM

Tosk is developing a family of inexpensive, small molecule drugs — what we call CompanionTM drugs — that when administered alongside certain cancer therapies such as methotrexate, doxorubicin, cisplatin, EGFR inhibitors and radiation — what we call parent therapies — will significantly improve patient outcomes, enhance dosing regimens and cut the cost of treating both cancer and toxic side effects that might occur.

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Product Pipeline

Tosk has patented two new pharmaceutical products and has two other preclinical-stage products in development.

TK-90: Our most advanced, patented drug, which recently completed human trials that achieved Proof of Concept, is targeted at mucositis side effect reduction. Mucositis is the painful inflammation and ulceration of the mucous membranes lining the mouth, throat, and digestive tract, usually as an adverse effect of chemotherapy or radiation. Mucositis is costly to treat and may result in affecting or even terminating optimum treatment. Oral mucositis, inflammation and ulceration that occurs in the mouth, is a common and often debilitating complication of cancer treatment. Mucositis in the gut can introduce a route of infection that can be debilitating and potentially fatal.

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Transforming Treatment

There were 1.7 million new cases of cancer and 600,000 cancer-related deaths in the U. S. last year. This is despite regular media reports of breakthroughs in treatment, such as monoclonal antibodies and immunotherapies, and many billions of dollars spent on cancer research. New approaches may have long-term promise, but the reality is, most cancers are still treated with drugs that are decades old.

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Tosk Technology

Tosk uses two proprietary drug discovery methods to identify potential CompanionTM drugs. Together, we call these methods OMDSM for Optimizing Marketed DrugsSM because they allow us to efficiently screen compounds for their potential to block the adverse side effects of prescription drugs, or make certain drugs effective in patients who currently do not benefit from therapy.

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Brian D. Frenzel, President and CEO

Mr. Frenzel has over 25 years experience as a biomedical company executive, including serving as CEO of Centaur Pharmaceuticals, CEO of Adeza Biomedical, CEO of Vesta Medical, and COO of Genelabs Technologies. Previously, Mr. Frenzel was director of corporate planning at Syntex Corporation, a principal at Booz, Allen & Hamilton, a consultant at the Boston Consulting Group, and a lieutenant in the United States Navy Nuclear Power Program. Mr. Frenzel holds a BS in physics and an MBA from Stanford University.

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Meet Our R&D Pros

The two scientists leading Tosk’s efforts to change the fundamental nature of cancer care were inspired to pursue science in one case by his dad, in another case, by his grandfather.

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