More than a dozen companies have shifted their focus towards the
Hormone Receptor positive (HR+), human epidermal growth factor receptor 2 (HER2) negative breast cancer therapeutic area. Some of them are Jiangsu HengRui Medicine Co., Odonate Therapeutics, Radius Pharmaceuticals, Immunomedics, Roche Group Syndax Pharmaceuticals, Merck Sharp & Dohme Corp, Eagle Pharmaceuticals and others. Tesetaxel is an investigational agent developed by Odonate Therapeutics, belongs to a class of drugs known as taxanes, which are widely used in the cancer treatment. This is an orally administered chemotherapy. Odonate is hoping to qualify as a New Chemical Entity (NCE) if and when a New Drug Application (NDA) is submitted, retains the same taxane core as the approved taxanes, but includes the addition of two novels, nitrogen-containing functional group. This new formulation does not contain solubilizing agents contained in other taxane formulations which are known to cause hypersensitivity reactions. This is currently being accessed in phase III.
Sacituzumab govitecan (IMMU-132: Immunomedics) is an advanced product candidate, which is a novel, first-in-class antibody-drug conjugate (ADC). Sacituzumab govitecan is an ADC that contains SN-38, the active metabolite of irinotecan, approved by many Health Authorities, including the US Food and Drug Administration (FDA) as a chemotherapeutic for patients with cancer. SN-38 cannot be given directly to patients because of its toxicity and poor solubility. Immunomedics produced Sacituzumab govitecan by conjugating SN-38 site-specifically and at a high ratio of drug to hRS7, our anti-TROP-2 antibody required for systemically administered pain medications like opioids that bears the risk of harmful side effects. The (FDA) US Food and Drug Administration had accepted the new drug application (NDA) for HTX-011 and also granted a Priority Review designation. Heron Therapeutics recently announced that the Marketing Authorization Application (MAA) HTX-011, for postoperative pain, was validated by the European Medicines Agency (EMA). This novel drug is currently is in Phase III clinical developmental stage. SHR6390 (Jiangsu HengRui Medicine) is Cyclin-dependent kinases 4 and 6 (CDK4/6) of cell cycle progression and are dysregulated in cancers. Inhibition of CDK4/6 induces G1 phase cell cycle arrest, therefore retards tumour growth. This inhibits retinoblastoma (Rb) protein phosphorylation early in the G1 phase, which prevents CDK-mediated G1-S phase transition and leads to cell cycle arrest. This suppresses DNA replication and decreases tumour cell proliferation. CDK4 and 6 are serine/threonine kinases that are up-regulated in many tumour cell types and play a vital role in the regulation of cell cycle progression. SHR6390 has been recently accessed in phase II clinical trials.
MM-121 is a potent engineered monoclonal antibody, which is designed to stop the HER3 pathway by halting the signal between heregulin and the HER3 receptor. The HER3 pathway, a drug tolerance pathway that allows cancer cells to sneak away death and sustain the effect of other drugs. Heregulin (HRG) activates the HER3 pathway that binds to the HER3 receptor. Merrimack has pioneered this pathway as a critical node in cellular signalling networks and a prime target for cancer drug development. EGL-5385-C-1701 (fulvestrant: Eagle Pharmaceuticals) is an estrogen-receptor antagonist. Fulvestrant binds to estrogen receptors, which are found in some breast cancer cells. These proteins may cause cancer cells to grow. Fulvestrant blocks these proteins and may keep cancer cells from growing. This is already approved the drug by the US FDA, hormone receptor (HR)-positive metastatic breast cancer treatment in postmenopausal women with disease progression following anti-estrogen therapy. This could be used for the treatment of HR-positive, human epidermal growth factor receptor 2 (HER2)-negative advanced or metastatic breast cancer in combination with palbociclib in women with disease progression after endocrine therapy.
Due to this high number of HR-positive/ HER2-negative Breast Cancer therapies, all are expected to be launched at nearly the same time; there will be an intense race among all these therapies. Therefore, no noteworthy difference in the HR-positive/ HER2-negative Breast Cancer market shares of these therapies has been observed, based on their launch time.