Durlobactam is a new member of the diazabicyclooctane class of beta-lactamase inhibitors with broad-spectrum activity against Ambler class A, C, and D serine beta-lactamases. Sulbactam is a first-generation beta-lactamase inhibitor with activity limited to a subset of class A enzymes that also has direct-acting antibacterial activity against Acinetobacter spp. The latter feature is due to sulbactam's ability to inhibit certain penicillin-binding proteins, essential enzymes involved in bacterial cell wall synthesis in this pathogen. Because sulbactam is also susceptible to cleavage by numerous beta-lactamases, its clinical utility for the treatment of contemporary Acinetobacter infections is quite limited. However, when combined with durlobactam, the activity of sulbactam is effectively restored against these notoriously multidrug-resistant strains. In May 2023, the FDA approved Innoviva’s antibiotic, sulbactam-durlobactam (Xacduro), for treatment in patients 18 years of age and older for the treatment of hospital-acquired bacterial pneumonia and ventilator-associated bacterial pneumonia (HABP/VABP) caused by susceptible isolates of ABC.

Elacestrant (ER-306323 or RAD 1901 [6R)-6-(2-(N-(4-(2-(ethylamino)ethyl)benzyl)-N-ethylamino)-4-methoxyphenyl)-5,6,7,8-tetrahydronaphthalen-2-ol dihydrochloride]) is an estrogen receptor antagonist that binds to estrogen receptor-alpha (ERα). In ERpositive (ER ) HER2-negative (HER2-) breast cancer cells, elacestrant inhibited 17β-estradiol mediated cell proliferation at concentrations inducing degradation of ERα protein mediated through proteasomal pathway. Elacestrant demonstrated in vitro and in vivo antitumor activity including in ER HER2- breast cancer models resistant to fulvestrant and cyclin-dependent kinase 4/6 inhibitors and those harboring estrogen receptor 1 gene (ESR1) mutations. On January 27, 2023, the Food and Drug Administration (FDA) approved elacestrant (Orserdu, Stemline Therapeutics, Inc.) for postmenopausal women or adult men with ER-positive, HER2-negative, ESR1-mutated advanced or metastatic breast cancer with disease progression following at least one line of endocrine therapy.

Leniolisib (JOENJA®) is an oral selective phosphoinositide 3-kinase-delta (PI3Kdelta) inhibitor being developed by Pharming Group NV in-licensed from Novartis for the treatment of immunodeficiency disorders. Leniolisib inhibits PI3K-delta by blocking the active binding site of PI3K-delta. In cell-free isolated enzyme assays, leniolisib was selective for PI3K-delta over PI3K-alpha (28-fold), PI3K-beta (43-fold), and PI3K-gamma (257-fold), as well as the broader kinome. In cell-based assays, leniolisib reduced pAKT pathway activity and inhibited proliferation and activation of B and T cell subsets. Gain-of-function variants in the gene encoding the p110-delta catalytic subunit or loss of function variants in the gene encoding the p85-alpha regulatory subunit each cause hyperactivity of PI3K-delta. Leniolisib inhibits the signalling pathways that lead to increased production of PIP3, hyperactivity of the downstream mTOR/AKT pathway, and to the dysregulation of B and T cells. In March 2023, leniolisib received its first approval for the treatment of activated PI3Kdelta syndrome (APDS) in adult and paediatric patients 12 years of age and older. Leniolisib is also under regulatory review in European Union for the treatment of APDS. Development of leniolisib for the treatment of Sjögren's syndrome has been discontinued.

Ponesimod is an experimental drug for the treatment of multiple sclerosis (MS) graft-versus-host disease and psoriasis. It acts on certain types of white blood cells (lymphocytes) which are involved in the autoimmune attack on myelin seen in multiple sclerosis (MS). Ponesimod is an orally active, reversible, and selective sphingosine-1-phosphate receptor (S1PR1) modulator. The drug is in phase II clinical trial for the treatment of graft-versus-host disease. In addition, the phase III clinical trial comparing ponesimod to teriflunomide in relapsing-remitting MS is ongoing.

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.

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.

Lurbinectedin (PM-01183) - is a synthetic tetrahydropyrrolo [4, 3, 2-de]quinolin-8(1H)-one alkaloid analogue with potential antineoplastic activity. Lurbinectedin covalently binds to residues lying in the minor groove of DNA, which may result in delayed progression through S phase, cell cycle arrest in the G2/M phase and cell death. Lurbinectedin is a novel anticancer agent currently undergoing late-stage (Phase II /III) clinical evaluation in platinum-resistant ovarian, BRCA1/2-mutated breast and small-cell lung cancer. Lurbinectedin is structurally related to trabectedin and it inhibits active transcription and the DNA repair machinery in tumour cells.

Opicapone (Ongentys®), a potent, oral, third-generation, long-acting, peripheral catechol-O-methyltransferase (COMT) inhibitor, is approved as the adjunctive treatment to levodopa (L-Dopa)/dopa-decarboxylase inhibitor (DDCI) therapy in adults with Parkinson's disease (PD) and end-of-dose motor fluctuations who cannot be stabilized on those combinations. Opicapone is a hydrophilic 1,2,4-oxadiazole analog with a pyridine N-oxide at position 3, with these modifications enhancing its potency and extending its duration of action, whilst avoiding cell toxicity. In preclinical animal studies, Opicapone-induced inhibition of peripheral (but not central) COMT activity was associated with a prolonged increase in systemic and central exposure to L-Dopa, with a corresponding reduction in 3-OMD exposure. Following single or multiple doses of Opicapone (5–1200 mg) in healthy adult volunteers or patients with PD, Opicapone inhibited COMT activity in ex vivo erythrocyte assays in a reversible dose-dependent manner, with the duration of Opicapone-induced COMT inhibition independent of dose. Adjunctive Opicapone was generally well tolerated during more than a year of treatment in BIPARK I and BIPARK II (double-blind plus extension phases). The recommended dosage is 50 mg once daily, which should be taken at bedtime at least 1 h before or after L-Dopa combinations.

Selumetinib (AZD6244 or ARRY-142886) is a potent, selective, and ATP-uncompetitive inhibitor of Ras-Raf-mitogen-activated protein kinase kinase (MEK1/2). This inhibition can prevent ERK activation, disrupt downstream signal transduction, and inhibit cancer cell proliferation and survival. Selumetinib has shown tumour suppressive activity in multiple rodent models of human cancer including melanoma, pancreatic, colon, lung, and breast cancers. AstraZeneca is responsible for development and commercialization of selumetinib.

Bremelanotide (formerly PT-141) was developed for the treatment of female sexual dysfunction, hemorrhagic shock, and reperfusion injury. Bremelanotide, a synthetic peptide analog of α-melanocyte-stimulating hormone (α-MSH) is an agonist at melanocortin receptors including the MC3R and MC4R, which are expressed primarily in the central nervous system. Bremelanotide originally was tested for intranasal administration in treating female sexual dysfunction but this application was temporarily discontinued in 2008 after concerns were raised over adverse side effects of increased blood pressure. It appears that development for hemorrhagic shock and reperfusion injury has been discontinued. Palatin Technologies licensed North American development and commercialization rights of bremelanotide to Amag in January 2017. In June 2018, the US Food and Drug Administration (FDA) accepted AMAG Pharmaceuticals’ new drug application for bremelanotide for treatment of hypoactive sexual desire disorder in premenopausal women. If approved, bremelanotide will be available as a self-administered, disposable subcutaneous auto-injector used in anticipation of a sexual encounter.