Pitolisant (INN) or tiprolisant (USAN) is a histamine receptor inverse agonist/antagonist selective for the H3 subtype. It has stimulant and nootropic effects in animal studies and may have several medical applications, having been researched for the treatment of narcolepsy, for which it has been granted orphan drug status in the EU and US. It is currently in clinical trials for schizophrenia and Parkinson’s disease. Pitolisant hydrochloride was approved by European Medicine Agency (EMA) on Mar 31, 2016. It was developed and marketed as Wakix® by Bioprojet in EU. Wakix® is available as the tablet for oral use, containing 4.5 mg and 18 mg of Pitolisant hydrochloride. The initial dose of 9 mg (two 4.5 mg, tablets) per day, and it should be used at the lowest effective dose, depending on individual patient response and tolerance, according to an up-titration scheme, without exceeding the dose of 36 mg/day. Pitolisant was the first clinically used H3 receptor inverse agonist.

Lusutrombopag (trade name Mulpleta) is an orally bioavailable, small molecule thrombopoietin (TPO) receptor agonist being developed by Shionogi for chronic liver disease (CLD) patients with thrombocytopenia prior to elective invasive surgery. Lusutrombopag acts selectively on the human TPO receptor and activates signal transduction pathways that promote the proliferation and differentiation of bone marrow cells into megakaryocytes, thereby increasing platelet levels. In September 2015, Lusutrombopag received its first global approval in Japan for the improvement of CLD-associated thrombocytopenia in patients scheduled to undergo elective invasive procedures. Oral Lusutrombopag is rapidly absorbed, with a median time to maximum serum concentration (Tmax) of 3.8–4.0 h in healthy subjects administered single doses of oral Lusutrombopag 1, 2 or 4 mg, and 6 h in CLD patients with thrombocytopenia administered oral Lusutrombopag 3 mg once daily for 7 days. The major metabolic pathway for Lusutrombopag appears to be omega- and beta-oxidation. Lusutrombopag is a substrate of breast cancer resistance protein and P-glycoprotein, according to in vitro data.

Naldemedine (Symproic) is an opioid antagonist indicated for the treatment of opioid-induced constipation (OIC) in adult patients with chronic non-cancer pain. Naldemedine is an opioid antagonist with binding affinities for mu-, delta-, and kappa-opioid receptors. Naldemedine functions as a peripherally-acting mu-opioid receptor antagonist in tissues such as the gastrointestinal tract, thereby decreasing the constipating effects of opioids. Naldemedine is a derivative of naltrexone to which a side chain has been added that increases the molecular weight and the polar surface area, thereby reducing its ability to cross the blood-brain barrier (BBB). Naldemedine is also a substrate of the P-glycoprotein (P-gp) efflux transporter. Based on these properties, the CNS penetration of naldemedine is expected to be negligible at the recommended dose levels, limiting the potential for interference with centrally-mediated opioid analgesia. Naldemedine was approved in 2017 in both the US and Japan for the treatment of Opioid-induced Constipation.

Rifampin is an antibiotic that inhibits DNA-dependent RNA polymerase activity in susceptible cells. Specifically, it interacts with bacterial RNA polymerase but does not inhibit the mammalian enzyme. It is bactericidal and has a very broad spectrum of activity against most gram-positive and gram-negative organisms (including Pseudomonas aeruginosa) and specifically Mycobacterium tuberculosis. It is FDA approved for the treatment of tuberculosis, meningococcal carrier state. Healthy subjects who received rifampin 600 mg once daily concomitantly with saquinavir 1000 mg/ritonavir 100 mg twice daily (ritonavir-boosted saquinavir) developed severe hepatocellular toxicity. Rifampin has been reported to substantially decrease the plasma concentrations of the following antiviral drugs: atazanavir, darunavir, fosamprenavir, saquinavir, and tipranavir. These antiviral drugs must not be co-administered with rifampin. Common adverse reactions include heartburn, epigastric distress, anorexia, nausea, vomiting, jaundice, flatulence, cramps.

Dovitinib is an orally active small molecule that exhibits potent inhibitory activity against multiple receptor tyrosine kinases (RTK) involved in tumor growth and angiogenesis. Dovitinib strongly binds to fibroblast growth factor receptor 3 (FGFR3) and inhibits its phosphorylation, which may result in the inhibition of tumor cell proliferation and the induction of tumor cell death. In addition, this agent may inhibit other members of the RTK superfamily, including the vascular endothelial growth factor receptor; fibroblast growth factor receptor 1; platelet-derived growth factor receptor type 3; FMS-like tyrosine kinase 3; stem cell factor receptor (c-KIT); and colony-stimulating factor receptor 1; this may result in an additional reduction in cellular proliferation and angiogenesis, and the induction of tumor cell apoptosis. There are several ongoing Phase I/III clinical trials for dovitinib.

Honokiol is a biphenolic natural product isolated from the bark and leaves of Magnolia plant spp. Honokiol possesses anti-carcinogenic, anti-inflammatory, anti-oxidative, anti-angiogenic as well as the inhibitory effect on malignant transformation of papillomas to carcinomas in vitro and in vivo animal models without any appreciable toxicity. Honokiol affects multiple signaling pathways, molecular and cellular targets including nuclear factor-κB (NF-κB), STAT3, epidermal growth factor receptor (EGFR), cell survival signaling, cell cycle, cyclooxygenase and other inflammatory mediators, etc. Honokiol can permeate the blood-brain barrier and the blood-cerebrospinal fluid to increase its bioavailability in neurological tissues. Diverse studies have provided evidence on the neuroprotective effect of honokiol in the central nervous system, due to its potent antioxidant activity, and amelioration of the excitotoxicity mainly related to the blockade of glutamate receptors and reduction in neuroinflammation. Honokiol can attenuate neurotoxicity exerted by abnormally aggregated Abeta in Alzheimer's disease. Honokiol is being developed by Huons as HL tablet for the treatment of alcoholic and non-alcoholic fatty liver.

Indirubin is derived from the Indigo Plant (Isatis Root, Isatis Leaf). It is used as part of a traditional Chinese herbal prescription called Dang Gui Long Hui Wan, to treat chronic myelogenous leukemia (CML). Indirubin inhibits DNA synthesis in several cell lines, in a cell-free assay and in vivo in rats with Walker-256 sarcoma. A weak binding of indirubin to DNA in vitro has been described. Indirubin inhibited all cyclin-dependent kinases (1,2,4,5) almost equally. Indirubin has been approved for clinical trials against chronic myelocytic and chronic granulocytic leukaemia. A few studies show that Indirubin is effective against psoriasis. Mild to severe nausea, vomiting, abdominal pain, diarrhea, headache, and edema are reported adverse events of Indirubin. Long-term oral ingestion has also occasionally been associated with hepatitis, pulmonary arterial hypertension and cardiac insufficiency.

Pitolisant (INN) or tiprolisant (USAN) is a histamine receptor inverse agonist/antagonist selective for the H3 subtype. It has stimulant and nootropic effects in animal studies and may have several medical applications, having been researched for the treatment of narcolepsy, for which it has been granted orphan drug status in the EU and US. It is currently in clinical trials for schizophrenia and Parkinson’s disease. Pitolisant hydrochloride was approved by European Medicine Agency (EMA) on Mar 31, 2016. It was developed and marketed as Wakix® by Bioprojet in EU. Wakix® is available as the tablet for oral use, containing 4.5 mg and 18 mg of Pitolisant hydrochloride. The initial dose of 9 mg (two 4.5 mg, tablets) per day, and it should be used at the lowest effective dose, depending on individual patient response and tolerance, according to an up-titration scheme, without exceeding the dose of 36 mg/day. Pitolisant was the first clinically used H3 receptor inverse agonist.

Naldemedine (Symproic) is an opioid antagonist indicated for the treatment of opioid-induced constipation (OIC) in adult patients with chronic non-cancer pain. Naldemedine is an opioid antagonist with binding affinities for mu-, delta-, and kappa-opioid receptors. Naldemedine functions as a peripherally-acting mu-opioid receptor antagonist in tissues such as the gastrointestinal tract, thereby decreasing the constipating effects of opioids. Naldemedine is a derivative of naltrexone to which a side chain has been added that increases the molecular weight and the polar surface area, thereby reducing its ability to cross the blood-brain barrier (BBB). Naldemedine is also a substrate of the P-glycoprotein (P-gp) efflux transporter. Based on these properties, the CNS penetration of naldemedine is expected to be negligible at the recommended dose levels, limiting the potential for interference with centrally-mediated opioid analgesia. Naldemedine was approved in 2017 in both the US and Japan for the treatment of Opioid-induced Constipation.

Rifampin is an antibiotic that inhibits DNA-dependent RNA polymerase activity in susceptible cells. Specifically, it interacts with bacterial RNA polymerase but does not inhibit the mammalian enzyme. It is bactericidal and has a very broad spectrum of activity against most gram-positive and gram-negative organisms (including Pseudomonas aeruginosa) and specifically Mycobacterium tuberculosis. It is FDA approved for the treatment of tuberculosis, meningococcal carrier state. Healthy subjects who received rifampin 600 mg once daily concomitantly with saquinavir 1000 mg/ritonavir 100 mg twice daily (ritonavir-boosted saquinavir) developed severe hepatocellular toxicity. Rifampin has been reported to substantially decrease the plasma concentrations of the following antiviral drugs: atazanavir, darunavir, fosamprenavir, saquinavir, and tipranavir. These antiviral drugs must not be co-administered with rifampin. Common adverse reactions include heartburn, epigastric distress, anorexia, nausea, vomiting, jaundice, flatulence, cramps.