Fostemsavir (BMS-663068) is an investigational attachment inhibitor with a unique mechanism of action. It is a prodrug of temsavir, which binds to HIV envelope glycoprotein 120 (gp120), thereby preventing viral attachment to the host CD4 cell surface receptor. In the absence of effective binding of HIV gp120 with the host CD4 receptor, HIV does not enter the host cell. Because fostemsavir has a novel mechanism of action, the drug should have full activity against HIV strains that have developed resistance to other classes of antiretroviral medications. In a phase 2b study of treatment-experienced individuals, fostemsavir appeared to be well tolerated. Phase 3 studies are ongoing.

Cortexolone 17α-propionate (WINLEVI, BREEZULA) is a steroid belonging to the family of cortexolone derivatives. It is a topical and peripherally selective androgen antagonist. WINLEVI is used for the treatment of acne and has completed Phase II clinical trials and Phase III trials. BREEZULA is used for the treatment of androgenic alopecia and is currently undergoing a Phase II trial in the US.

Setmelanotide (IMCIVREE™) is a melanocortin-4 (MC4) receptor agonist developed by Rhythm Pharmaceuticals (Rhythm) for the treatment of ultrarare genetic disorders of obesity. Setmelanotide was approved on 27 November 2020 in the USA as a subcutaneous (SC) injectable formulation for chronic weight management in adult and pediatric patients 6 years of age and older with obesity due to proopiomelanocortin (POMC), proprotein convertase subtilisin/kexin type 1 (PCSK1), or leptin receptor (LEPR) deficiency confirmed by genetic testing demonstrating variants in POMC, PCSK1, or LEPR genes that are interpreted as pathogenic, likely pathogenic, or of uncertain significance (VUS). Rhythm are also developing the drug for the treatment of obesity associated with other rare genetic disorders including Bardet–Biedl Syndrome, Alström Syndrome, POMC and other MC4R pathway heterozygous defciency obesities, and POMC epigenetic disorders.

Berotralstat (ORLADEYO™; BCX7353) is an orally administered kallikrein inhibitor, which has been developed by BioCryst Pharmaceuticals for hereditary angioedema (HAE). The inhibition of kallikrein by berotralstat decreases the production of bradykinin, which prevents the localised tissue oedema that occurs during attacks of HAE. Berotralstat has been approved in the USA, and subsequently in Japan, for prophylaxis to prevent attacks of HAE in adults and paediatric patients aged 12 years or older.

Pralsetinib (GAVRETO™, Blueprint Medicines Corporation) is an orally-administered, next-generation, small-molecule selective rearranged during transfection (RET) inhibitor being developed for the treatment of various solid tumours. RET is a well described proto-oncogene present in multiple cancers including non-small cell lung cancer (NSCLC), papillary thyroid cancer, and medullary thyroid carcinoma. Pralsetinib is a kinase inhibitor of wild-type RET and oncogenic RET fusions (CCDC6-RET) and mutations (RET V804L, RET V804M and RET M918T) with half maximal inhibitory concentrations (IC50s) less than 0.5 nM. In purified enzyme assays, pralsetinib inhibited DDR1, TRKC, FLT3, JAK1-2, TRKA, VEGFR2, PDGFRb, and FGFR1 at higher concentrations that were still clinically achievable at Cmax. In cellular assays, pralsetinib inhibited RET at approximately 14-, 40-, and 12-fold lower concentrations than VEGFR2, FGFR2, and JAK2, respectively. Pralsetinib is approved for the treatment of RET fusion-positive metastatic NSCLC. In the pivotal phase I/II ARROW trial, pralsetinib demonstrated rapid and durable anti-tumour activity in patients with advanced RET fusion-positive NSCLC who were previously treated with platinum-based chemotherapy or were treatment-naïve. Pralsetinib also showed clinical activity against intracranial metastases arising from NSCLC. Pralsetinib had a manageable tolerability profile, with the most common grade 3 treatment-related adverse events being neutropenia, hypertension, anaemia and decreased white blood cell count.

Tazemetostat (EPZ-6438) is a selective inhibitor of histone-lysine N-methyltransferase EZH2. The drug is under clinical development (phase II) for the treatment of Diffuse Large B Cell Lymphoma, Malignant Mesothelioma and Synovial Sarcoma.

TUCATINIB (ONT-380 or ARRY-380) is an orally active, reversible and selective small-molecule HER2 inhibitor invented by Array and licensed to Cascadian Therapeutics (previously named Oncothyreon) for development, manufacturing and commercialization. HER2, a growth factor receptor that is over-expressed in multiple cancers, including breast, ovarian, and stomach cancer. HER2 mediates cell growth, differentiation and survival, and tumors that overexpress HER2 are more aggressive and historically have been associated with poorer overall survival compared with HER2-negative cancers. ONT-380 is highly active as a single agent and in combination with both chemotherapy and Herceptin® (trastuzumab) in xenograft models of HER2+ breast cancer, including models of CNS metastases that were refractory to Tykerb® (lapatinib) or neratinib treatment. In a Phase 1 single agent clinical study, ONT-380 administered orally twice a day was well tolerated and demonstrated anti-tumor activity in heavily pre-treated HER2+ breast cancer patients with metastatic disease. Based on the strength of these preclinical and clinical trials, ONT-380 is advancing in one Phase 2 and three Phase 1b combination trials in patients with metastatic breast cancer. A second study reported the CNS activity of ONT-380 in combination with either T-DM1 or trastuzumab or capecitabine. Patients with brain metastases assessable for response were included in the combined analysis. Responses and clinical benefit in the CNS were reported with the three combinations tested, supporting future development of the drug for this particular indication.

Osilodrostat (INN, USAN) (developmental code name LCI-699) is an orally active, non-steroidal corticosteroid biosynthesis inhibitor which is under development by Novartis for the treatment of Cushing's syndrome and pituitary ACTH hypersecretion (a specific subtype of Cushing's syndrome). Osilodrostat specifically acts as a potent and selective inhibitor of aldosterone synthase (CYP11B2) and at higher dosages of 11β-hydroxylase (CYP11B1). Osilodrostat decreases plasma and urinary aldosterone levels and rapidly corrects hypokalemia, in patients with primary aldosteronism and hypertension. At doses ≥1 mg o.d. Osilodrostat markedly increases 11-deoxycortisol plasma levels and blunts ACTH-stimulated cortisol release in ≈20% of patients, consistent with the inhibition of CYP11B1. In patients with resistant hypertension, Osilodrostat produces a non-significant reduction in blood pressure, possibly due to the increase in 11-deoxycortisol levels and the stimulation of the hypothalamic-pituitary-adrenal feedback axis. Because of the lack of selectivity, poor antihypertensive effect, and short half-life, the development of Osilodrostat as antihypertensive was halted. As of 2017, Osilodrostat is in phase III and phase II clinical trials for the treatment of pituitary ACTH hypersecretion and Cushing's syndrome, respectively.

Vibegron is a selective beta 3 adrenergic receptor (β3AR) agonist that is being developed in Japan jointly by Kyorin Pharmaceutical Co., Ltd and Kissei Pharmaceutical Co., Ltd and in other regions worldwide (except in several other Asian countries) by Urovant Sciences for the treatment of overactive bladder (OAB). Vibegron potently activates human b3AR and increases cAMP levels, with an EC50 of 1.1 nM. Based on results from Japanese phase III trials, vibegron received approval in Japan in September 2018 for this indication. Vibegron, an active ingredient of Beova® Tablets, is a novel once-daily oral treatment for overactive bladder (OAB), acts selectively on the bladder's β3-adrenergic receptor, relaxes the bladder and enhances the urine collection, and consequently improves the symptoms of urgency, urinary frequency and urge urinary incontinence associated with OAB. On December 23, 2020 the FDA approved vibegron (Gemtesa) for the treatment of adult patients with overactive bladder (OAB) with symptoms of urge urinary incontinence (UUI), urgency, and urinary frequency.

Nifurtimox is a nitrofuran derivative used as a primary agent in the treatment of American trypanosomiasis (Chagas' disease) caused by Trypanosoma cruzi, especially in the acute, early stage of the disease. The efficacy of nifurtimox in the treatment of chronic Chagas' disease varies from one country to another, possibly due to variation in the sensitivity of different strains of the organism. Nifurtimox has also been used to treat African trypanosomiasis (sleeping sickness) and is active in the second stage of the disease (central nervous system involvement). When nifurtimox is given on its own, about half of all patients will relapse, but the combination of melarsoprol with nifurtimox appears to be efficacious. Nifurtimox forms a nitro-anion radical metabolite that reacts with nucleic acids of the parasite causing significant break down of DNA. Nifurtimox undergoes reduction and creates oxygen radicals such as superoxide. These radicals are toxic to T. cruzi. Mammalian cells are protected by the presence of catalase, glutathione, peroxidases, and superoxide dismutase. Accumulation of hydrogen peroxide to cytotoxic levels results in parasite death. Side effects occur following chronic administration, particularly in elderly people. Major toxicities include immediate hypersensitivities such as anaphylaxis and delayed hypersensitivity reaction involving icterus and dermatitis. Central nervous system disturbances and peripheral neuropathy may also occur.