Repurposed Drugs

Finding New Purposes for Established or Abandoned Therapeutics

It's a wonder new medication are ever developed at all. Taking a new drug from promising molecule to marketable product can cost upwards of a billion dollars and take a decade or more to move from clinical trials to approval. Oh, and the overall failure rate hovers near 95%.

Not surprisingly, the drug industry has become interested in repurposing drugs, which involves testing a medication for a therapeutic use different from its original intended use. These can be drugs already on the market, or those that didn’t pan out for their original intended use.

Well-known repositioned drug success stories include:

  • Rogaine, the hair regrowth treatment, which was developed from the oral blood pressure medication minoxidil after researchers noticed that hair growth was a common side effect.
  • Thalidomide, which was taken off the market in 1961 after being discovered to cause severe birth defects, but approved again by the FDA in 1998 for use in leprosy and again in 2006 for multiple myeloma
  • Viagra, which was developed to treat pulmonary arterial hypertension before gaining approval in 1998 to treat erectile dysfunction.

Emory's OTT already has several repurposed drug candidates in development to treat various conditions.

DHAA and Derivatives for Treatment of BRAF-V600E-Positive Cancer: Melanoma is the deadliest form of skin cancer in the US. Surgical strategies followed by chemotherapy and immunology often have a high successful rate; however, patients with a gene mutation sensitive to the patient’s diet, such as BRAF V600E mutant, may need an alternative form of treatment. Emory inventors have discovered that dehydroacetic acid (DHAA), used in cosmetics and food preservation, can help reduce the tumor size in an animal model and show no visible toxicity. Hence, DHAA could potentially be used in cancer therapeutics as an alternative treatment of BRAF V600E positive forms of cancer. (Techid: 16067; view our technology brief)

Epsilon aminocaproic acid, or EACA, was initially developed by Hanna J. Khoury, MD, who was a professor at the Emory School of Medicine, and Ana G. Antun, MD, a staff physician at the Emory School of Medicine in the Department of Hematology, as an antifibrinolytic agent to treat hemorrhage in patients with congenital bleeding disorders. EACA was also found to be a cheaper and more easily administered alternative to platelet replacement therapy. As a common, orally bioavailable FDA-approved drug, EACA is a safe and highly effective treatment alternative for patients with severe and chronic thrombocytopenia. Thrombocytopenia is a condition characterized by low platelet counts as a result of chemotherapy, which tends to kill off blood-forming cells in bone marrow. Excessive bleeding is a common problem in those with leukemia and bone marrow failure, and administration of EACA has been found to be clinically superior to standard platelet transfusions as treatment. (Techid: 13023; view our technology brief)

Small Molecules that Promote Osteogenesis: Bone grafting, or transplanting of bone tissues, is a growing market with a value of 2.6 billion dollars per year worldwide. Current treatments requiring a high concentration of bone morphogenetic proteins (BMP) can result in high costs, adverse side effects and set a high bar for routine clinical use. Emory researchers have found several repurposed small molecules as substitutes for BMP. The molecules have shown activity in a cell-based assay, enhancing suboptimal doses of BMP. These repurposed small molecules have been FDA approved for other indications, have lower cost, and may be administered locally, reducing adverse side effects. (Techids: 11221 & 12148; view our technology brief)

Imatinib is a protein tyrosine kinase inhibitor that was initially marketed as an anti-cancer therapeutic and has now been repurposed by Emory School of Medicine researcher Daniel Kalman, PhD as an effective treatment for multidrug-resistant varieties of Tuberculosis, or MDR-TB. MDR-TB is a variant of Tuberculosis that poses an increased threat to exposed populations, as the majority of first line of defense drugs prove to be ineffective as potential treatment options. MDR-TB uses intracellular protein kinases to enter and survive within macrophages in the body, ultimately escaping the body’s innate immune system. Imatinib has been proven to reduce bacterial loads in macrophages, particularly when used to combat rifampin-resistant strains of Tuberculosis. (Techid: 16002; view our technology brief)

PLK1 Inhibitors for the Diagnosis and Treatment of Small Cell Lung Carcinoma (SCLC): Emory inventor, Taofeek Owonikoko, has found that patients with a specific TP53 gene mutation have favorable response to PLK1 inhibitors in the treatment of Small Cell Lung Carcinoma (SCLC). SCLC is an aggressive form of lung cancer that happens often in smokers and has a high rate of recurrence in a short time period. Despite the good response to chemotherapy drugs at the initial stage, SCLC patients lack effective therapeutics due to resistance when relapse occurs. Unlike other chemotherapy treatments, PLK1 inhibitors overcome the drug-resistance of recurrent SCLC in patients with the TP53 gene mutation, which may also be used as a predictive biomarker to identify patients with sensitivity to PLK1 inhibitors. (Techid: 15128; view our technology brief)

A combination of rapamycin and the drug imatinib (Gleevec), used in the treatment of chronic myeloid leukemia, was found by researcher Jack Arbiser, MD, PhD, in dermatology, to be highly effective in decreasing tumors in mouse models of tuberous sclerosis (TS), a genetic disorder that causes non-malignant tumors to form in many different organs, primarily the brain, eyes, heart, kidney, skin, and lungs. The combination was found to be far better in preventing tumor growth than either drug alone. (Techid: 11050; view our technology brief)

Monoclonal Antibody for the Treatment of Non-alcoholic Steatohepatitis (NASH) and Liver Fibrosis: Recently, Emory scientists have begun researching what could become the first FDA approved drug for treating non-alcoholic steatohepatitis (NASH). The researchers demonstrated that monoclonal antibody Vedolizumab, generally used in treatment for ulcerative colitis or Crohn’s disease, could offer an effective treatment option for patients suffering from NASH, non-alcoholic fatty liver disease (NAFLD), or liver fibrosis. This treatment works by blocking the migration of inflammatory cells in patients with these specific liver diseases. Vedolizumab has already been tested and shown to be safe in patients, and this data will significantly impact its approval time. (Techid: 17155; view our technology brief)

Combination Therapy for Increasing Venetoclax Sensitivity in Multiple Myeloma: Multiple Myeloma (MM) is a cancer of the plasma cells and the second most common blood cancer. While there are various treatments for MM, treatment-resistant MM is common, and more than 20% patients succumb to aggressive treatment resistance disease soon after their diagnosis. Venetoclax is a treatment for Multiple Myeloma that induces cell death in MM cells. The use of the inhibitor succinate ubiquinone reductase (SQR) has been identified by Emory researchers to serve as a predictive marker for venetoclax sensitivity, and co-therapy with an SQR inhibitor and venetoclax has been shown to increase patient response to venetoclax. SQR inhibitors could help work against venetoclax resistant myeloma cells and eventually result in MM cell death where patients might otherwise become treatment resistant. (Techid: 17233; view our technology brief)

Combination Therapy for Treatment of Pediatric Brain Tumors: Researchers at Emory are developing a therapy for medulloblastoma (MB), the most common cancerous brain tumor that impacts children, by combining the inhibition of STAT3, a transcription factor, and YB-1, a protein. STAT3 and YB-1 play critical roles in MB, from cancer initiation, progression, and metastasis to chemoresistance and immune evasion. They are both highly expressed in all of the four subgroups of MB. The work in combining these treatments helps improve treatment while allowing more personalized, sub-group treatments for MB. The inhibition of each has been shown to inhibit colony formation and induce tumor cell death. Importantly, the co-therapy showed greater efficacy than when each drug was given separately. (Techid: 18166, view our technology brief)

Drug Combination to Treat Lung Cancer Metastasis: Emory inventors Malathy Shanmugam and Adam Marcus have developed a drug combination for the treatment of metastatic lung cancer, the leading cause of cancer deaths in the United States. Through research on metastatic cancer, it was discovered that metastatic cells come in collective packs of invasive cells than can be further distinguished as leaders and followers. In a study, Emory researchers found metabolic differences in leader and follower cells. Namely, leader cells rely on active pyruvate dehydrogenase (PDH) and follower cells, among other things, rely on glucose transporter 1 (GLUT1) expression. Therefore, this drug combines Alexidine dihydrochloride or CPI-613/devimistat (PDH inhibitors) and BAY-876 (GLUT1 inhibitor). The drug combination impacts both leader and follower cells, showing effective inhibition of these invasive packs of metastatic cancer cells. (Techid: 19171; view our technology brief)

HDAC Inhibitors for Managing Vascular Conditions and Diabetic Peripheral Neuropathies : The epigenetic modulators histone deacetylase inhibitors (HDACis), previously tested for use in cancer treatment, have been identified by Emory researchers as a treatment for diabetic neuropathy. A serious complication of diabetes mellitus, diabetic neuropathy impacts around 50% of type 1 and 2 diabetes patients. HDACis can serve to restore defective gene expressions involved in cellular processes such as cell cycle control, invasion/metastasis, apoptosis. By targeting HDACis like FDA approved vorinostat and belinostat at Schwann cells, DRG neurons, and endothelial cells, all of which are involved in diabetic neuropathy, repressed gene expression caused by diabetic conditioning increased. The treatment ameliorates many issues and symptoms associated with diabetic neuropathy. Direct HDACi injections have the potential to restore vascular and nerve function to patients with diabetic neuropathy.  (Techid: 17081, view our technology brief)

Transcriptomic-Driven Treatment for Cocaine Use Disorder (CUD): Despite the far-reaching and devastating effects of cocaine use disorder (CUD), there are currently no approved medications for CUD. Emory inventors are in the developmental stages of repurposing drugs for transcriptomic-driven treatment of the disorder. The researchers proposed that if a compound has a transcriptional signature that is opposed to a diseased state, then the compound could reverse the underlying disease mechanisms back to normal. Based on this, the inventors have identified and tested repurposed medications that are negatively associated to the neuropathology in human CUD. The data shows that the compounds have reversed CUD genes in neuronal cells and are outperforming current targets. With the substantial morbidity and mortality associated with cocaine use disorder, these medications could provide invaluable options for the many CUD patients who do not respond to psychosocial treatments. (Techid: 20204; view our technology brief)

Repurposing Small Molecules to Promote Bone Growth: Emory researchers have uncovered the possibility of repurposing small molecules for regenerative bone therapy. Currently, the options for such therapies in orthopedic surgery are bone grafting or recombinant human BMP treatment. However, each comes with issues. The best option for bone grafting can involve long-term pain from bone sample extraction from patients, while recombinant human BMP treatment is expensive and can have serious side effects. Small molecules fluticasone (F1) and valproic avid (VA1) inhibit sclerostin, which increases BMP efficiency of promoting osteogenesis. Repurposing these small molecules provides valuable opportunities to improve current treatments. These molecules are cheaper than any current options, and they do not require specialized delivery carriers.  (Techid: 19012; view our technology brief)

Therapeutic Compounds for Cardiomyocyte Proliferation and Cardiac Regeneration: Heart failure is a vast and deadly problem, and about 50% who develop it will die within five years of diagnosis. Current treatments for heart failure lack a strategy to rebuild heart muscle lost from an ischemic event. Emory scientists have identified a novel molecular pathway of cardiomyocyte (CM) cell replication. Specifically, they identified compounds that activate cell cycle re-entry, induce growth factors, amplify mitogenic response, and promote cell replication to build heart muscle. The administration of these repurposed compounds could allow rebuilding of heart muscle in patients with a congenital heart defect or myocardial injuries, addressing a serious problem in the treatment of heart failure. (Techid: 18222, 19110; view our technology brief)