Rifamycin SV is a derivative of antibiotic rifamycin B (the natural fermentation product of S. mediterranei broths). The primary target of rifampicin on whole bacteria is the synthesis of RNA. Rifamycin belongs to the ansamycin class of antibacterial drugs and acts by inhibiting the beta subunit of the bacterial DNA-dependent RNA polymerase, blocking one of the steps in DNA transcription. This results in inhibition of bacterial synthesis and consequently growth of bacteria. Rifampicin exhibits bactericidal activity on Gram-positive and Gram-negative bacteria and on mycobacteria. Rifamycin SV MMX® (AEMCOLO), a non-absorbable rifamycin antibiotic formulated using the multi-matrix system, was designed to exhibit its pharmacological action on the distal small intestine and colon. AEMCOLO is indicated for the treatment of travelers’ diarrhea (TD) caused by non-invasive strains of Escherichia coli in adults.

Macimorelin (AEZS 130) is an orally active, small-molecule, peptidomimetic growth hormone secretagogue receptor (GHSR1A) agonist (ghrelin analogue), being developed by AEterna Zentaris for the diagnosis of adult growth hormone deficiency (AGHD; somatotropin deficiency), and for the treatment of cachexia associated with chronic disease such as AIDS and cancer. Macimorelin was approved by the FDA in December 2017 under the market name Macrilen for oral solution. Macimorelin stimulates GH release by activating growth hormone secretagogue receptors present in the pituitary and hypothalamus. Macimorelin has been granted orphan drug designation by the FDA for diagnosis of AGHD.

Lesinurad (brand name Zurampic) is a urate transporter inhibitor for treating hyperuricemia associated with gout in patients who have not achieved target serum uric acid levels with a xanthine oxidase inhibitor alone. In gout patients, Lesinurad lowered serum uric acid levels and increased renal clearance and fractional excretion of uric acid. Following single and multiple oral doses of Lesinurad to gout patients, dose-dependent decreases in serum uric acid levels and increases in urinary uric acid excretion were observed. Lesinurad reduces serum uric acid levels by inhibiting the function of transporter proteins involved in uric acid reabsorption in the kidney. Lesinurad inhibited the function of two apical transporters responsible for uric acid reabsorption, uric acid transporter 1 (URAT1) and organic anion transporter 4 (OAT4), with IC50 values of 7.3 and 3.7 µM, respectively. URAT1 is responsible for the majority of the reabsorption of filtered uric acid from the renal tubular lumen. OAT4 is a uric acid transporter associated with diuretic-induced hyperuricemia. Lesinurad does not interact with the uric acid reabsorption transporter SLC2A9 (Glut9), located on the basolateral membrane of the proximal tubule cell. Based on in vitro studies, lesinurad is an inhibitor of OATP1B1, OCT1, OAT1, and OAT3; however, lesinurad is not an in vivo inhibitor of these transporters. In vivo drug interaction studies indicate that lesinurad does not decrease the renal clearance of furosemide (substrate of OAT1/3), or affect the exposure of atorvastatin (substrate of OATP1B1) or metformin (substrate of OCT1). Based on in vitro studies, lesinurad has no relevant effect on P-glycoprotein.

Indacaterol is an ultra-long-acting beta-adrenoceptor agonist developed by Novartis. It was approved by the European Medicines Agency (EMA) under the trade name Onbrez Breezhaler on November 30, 2009, and by the United States Food and Drug Administration (FDA), under the trade name Arcapta Neohaler, on July 1, 2011. It needs to be taken only once a day, unlike the related drugs formoterol and salmeterol. It is licensed only for the treatment of chronic obstructive pulmonary disease (COPD) (long-term data in patients with asthma are thus far lacking). It is delivered as an aerosol formulation through a dry powder inhaler.

Rapacuronium bromide (RAPLON), a nondepolarizing neuromuscular blocking agent, is a negative allosteric modulator of muscarinic acetylcholine receptors. Rapacuronium bromide is indicated as an adjunct to general anesthesia to facilitate tracheal intubation and to provide skeletal muscle relaxation during surgical procedures. There were no specific pharmacokinetic studies conducted to examine the drug-drug interactions of RAPLON. Due to the risk of fatal bronchospasm, it was withdrawn from the United States market less than 2 years after its FDA approval.

Trimetrexate, a second-generation folate antagonist which was used under brand name NEUTREXIN with concurrent leucovorin administration (leucovorin protection) was indicated as an alternative therapy for the treatment of moderate-to-severe Pneumocystis carinii pneumonia (PCP) in immunocompromised patients, including patients with the acquired immunodeficiency syndrome (AIDS). Nevertheless, this product was discontinued. In present time, trimetrexate with a different combinations is in the phase II of clinical trial for the treatment the following cancer diseases: pancreatic cancer and colorectal cancer (in combination with fluorouracil and leucovorin) and to treat a refractory acute leukemia in combination with leucovorin. Trimetrexate is a competitive inhibitor of dihydrofolate reductase (DHFR) from bacterial, protozoan, and mammalian sources. DHFR catalyzes the reduction of intracellular dihydrofolate to the active coenzyme tetrahydrofolate. Inhibition of DHFR results in the depletion of this coenzyme, leading directly to interference with thymidylate biosynthesis, as well as inhibition of folate-dependent formyltransferases, and indirectly to inhibition of purine biosynthesis. The result is disruption of DNA, RNA, and protein synthesis, with consequent cell death.

Trimetrexate, a second-generation folate antagonist which was used under brand name NEUTREXIN with concurrent leucovorin administration (leucovorin protection) was indicated as an alternative therapy for the treatment of moderate-to-severe Pneumocystis carinii pneumonia (PCP) in immunocompromised patients, including patients with the acquired immunodeficiency syndrome (AIDS). Nevertheless, this product was discontinued. In present time, trimetrexate with a different combinations is in the phase II of clinical trial for the treatment the following cancer diseases: pancreatic cancer and colorectal cancer (in combination with fluorouracil and leucovorin) and to treat a refractory acute leukemia in combination with leucovorin. Trimetrexate is a competitive inhibitor of dihydrofolate reductase (DHFR) from bacterial, protozoan, and mammalian sources. DHFR catalyzes the reduction of intracellular dihydrofolate to the active coenzyme tetrahydrofolate. Inhibition of DHFR results in the depletion of this coenzyme, leading directly to interference with thymidylate biosynthesis, as well as inhibition of folate-dependent formyltransferases, and indirectly to inhibition of purine biosynthesis. The result is disruption of DNA, RNA, and protein synthesis, with consequent cell death.

Metipranolol is a beta-adrenergic antagonist effective for both beta-1 and beta-2 receptors. It is used as an antiarrhythmic, antihypertensive, and antiglaucoma agent. Metipranolol blocks beta1 and beta2 (non-selective) adrenergic receptors. It does not have significant intrinsic sympathomimetic activity, and has only weak local anesthetic (membrane-stabilizing) and myocardial depressant activity. Orally administered beta-adrenergic blocking agents reduce cardiac output in both healthy subjects and patients with heart disease. In patients with severe impairment of myocardial function, beta-adrenergic receptor antagonists may inhibit the sympathetic stimulatory effect necessary to maintain adequate cardiac output. Metipranolol when applied topically in the eye, has the action of reducing elevated as well as normal intraocular pressure (IOP), whether or not accompanied by glaucoma. Elevated intraocular pressure is a major risk factor in the pathogenesis of glaucomatous visual field loss. The higher the level of intraocular pressure, the greater the likelihood of glaucomatous visual field loss and optic nerve damage. The primary mechanism of the ocular hypotensive action of Metipranolol is most likely due to reduction in aqueous humor production. A slight increase in outflow may be an additional mechanism. Metipranolol reduces IOP with little or no effect on pupil size or accommodation. Metipranolol is known as the brand OptiPranolol. Brand-name OptiPranolol is manufactured by Bausch & Lomb Incorporated. However, the patents for OptiPranolol have expired, and this medication is currently available in generic form. Generic OptiPranolol eye drops are available in one strength -- metipranolol 0.3 percent solution. It is made by Falcon Pharmaceuticals.

Pirbuterol (trade name Maxair) is a short-acting β2 adrenoreceptor agonist with bronchodilating action used in the treatment of asthma. The pharmacologic effects of beta-adrenergic agonist drugs, including pirbuterol, are at least in proof attributable to stimulation through beta-adrenergic receptors of intracellular adenyl cyclase, the enzyme which catalyzes the conversion of adenosine triphosphate (ATP) to cyclic-adenosine monophosphate (c-AMP). Increased c-AMP levels are associated with relaxation of bronchial smooth muscle and inhibition of release of mediators of immediate hypersensitivity from cells, especially from mast cells. Pirbuterol is used in asthma for reversal of acute bronchospasm, and also as a maintenance medication to prevent future attacks. It should be used in patients 12 years of age and older with or without concurrent theophylline and/or inhaled corticosteroid. After inhalation of doses up to 800 μg (twice the maximum recommended dose) systemic blood levels of pirbuterol are below the limit of assay sensitivity (2–5 ng/ml). A mean of 51% of the dose is recovered in urine as pirbuterol plus its sulfate conjugate following administration by aerosol. Pirbuterol is not metabolized by catechol-O-methyltransferase.

Guanabenz, an antihypertensive agent for oral administration-, is an aminoguanidine derivative, 2,'6-dichlorobenzylideneamina-guanidine acetate. It is white to an almost white powder having not more than a slight odor. Sparingly soluble in water and in 0.1 N hydrochloric acid; soluble in alcohol and in propylene glycol. Guanabenz is an orally active central alpha-2 adrenergic agonist. Its antihypertensive action appears to be mediated via stimulation of central alpha-adrenergic receptors, resulting in a decrease of sympathetic outflow from the brain at the bulbar level to the peripheral circulatory system. In clinical trials, guanabenz acetate, given orally to hypertensive patients, effectively controlled blood pressure without any significant effect on glomerular filtration rate, renal blood flow, body fluid volume or body weight. The Myelin Repair Foundation and the National Institutes of Health (National Institute of Neurological Disorders and Stroke) are developing guanabenz for the treatment of multiple sclerosis. Unlike the currently available treatment for multiple sclerosis that suppresses the immune system, guanabenz, an FDA approved the drug for the treatment of high blood pressure, has a potential to reduce the loss of myelin by protecting and repairing myelin-producing cells in the brain from damage. Phase I development is underway in the US.