Phase II drugs that target cholinergic receptors for the treatment of overactive bladder

Overactive bladder (OAB) is a term used to describe the symptom syndrome of urgency, with or without urgency incontinence, usually associated with frequency and nocturia. Antimuscarinics are the most widely prescribed class of drugs for OAB, although their systemic adverse effects limit their use in clinical practice as compliance. This has led to developments in the field.

In this review, the authors describe Phase II drugs that target cholinergic receptors. First, the authors present the new antimuscarinics (tarafenacin and afacifenacin). This is followed by reports on a combination drug (tolenix) containing a muscarinic antagonist (tolterodine) associated with a muscarinic agonist (pilocarpine). Further, the authors discuss the trials of well-known drugs in either new combination therapy (solifenacin and mirabegron) or with new routes of delivery (oxybutynin vaginal ring). Finally, the authors examine the option of targeting nicotinic acetylcholine receptors (dexmecamylamine).

Different strategies have been adopted to improve the efficacy and tolerability of therapeutics for OAB. Nicotinic receptors represent a novel therapeutic target; however, it is unlikely that antimuscarinic agents will be replaced as standard first-line therapy in the near future.