Prucalopride
Encyclopedia
Prucalopride is a drug acting as a selective, high affinity 5-HT4 receptor
agonist
which targets the impaired motility associated with chronic constipation
, thus normalising bowel movements. Prucalopride was approved for use in Europe in 2009, but it has not been approved by the Food and Drug Administration
for use in the United States.
(5-HT4
) receptor agonist with enterokinetic activities. Prucalopride alters colonic motility patterns via serotonin 5-HT4 receptor stimulation: it stimulates colonic mass movements, which provide the main propulsive force for defecation
.
The observed effects are exerted via highly selective action on 5-HT4 receptors: prucalopride has >150-fold higher affinity for 5-HT4 receptors than for other receptors. Prucalopride differs from other 5-HT4 agonists such as tegaserod
and cisapride
, which at therapeutic concentrations also interact with other receptors (5-HT1B/D and the cardiac human ether-a-go-go K+ channel
respectively) and this may account for the adverse cardiovascular events that have resulted in the restricted availability of these drugs. Clinical trials evaluating the effect of prucalopride on QT interval and related adverse events have not demonstrated significant differences compared with placebo.
attained 2–3 hours after single 2 mg oral dose) and is extensively distributed. Metabolism
is not the major route of elimination. In vitro, human liver metabolism is very slow and only minor amounts of metabolite
s are found. A large fraction of the active substance is excreted unchanged (about 60% of the administered dose in urine
and at least 6% in faeces). Renal excretion of unchanged prucalopride involves both passive filtration and active secretion. Plasma clearance averages 317 ml/min, terminal half-life is 24–30 hours, and steady-state is reached within 3–4 days. On once daily treatment with 2 mg prucalopride, steady-state plasma concentrations fluctuate between trough and peak values of 2.5 and 7 ng/ml, respectively.
In vitro data indicate that prucalopride has a low interaction potential, and therapeutic concentrations of prucalopride are not expected to affect the CYP-mediated metabolism of co-medicated medicinal products.
, abdominal, and rectal symptoms associated with chronic constipation). Infrequent bowel movements, bloating
, straining, abdominal pain
, and defecation urge with inability to evacuate can be severe symptoms, significantly affecting quality of life.
In three large clinical trials, 12 weeks of treatment with prucalopride 2 and 4 mg/day resulted in a significantly higher proportion of patients reaching the primary efficacy endpoint of an average of ≥3 spontaneous complete bowel movements than with placebo
. There was also significantly improved bowel habit and associated symptoms, patient satisfaction with bowel habit and treatment, and HR-QOL in patients with severe chronic constipation, including those who did not experience adequate relief with prior therapies (>80% of the trial participants). The improvement in patient satisfaction with bowel habit and treatment was maintained during treatment for up to 24 months; prucalopride therapy was generally well tolerated.
and gastrointestinal symptoms (abdominal pain, nausea
or diarrhoea). Such reactions occur predominantly at the start of therapy and usually disappear within a few days with continued treatment.
of chronic constipation in women in whom laxatives fail to provide adequate relief. The recommended dosage in adults is 2 mg administered orally once daily; exceeding this dosage is not expected to increase efficacy. The recommended starting dose in elderly patients (>65 years) is 1 mg once daily; thereafter the dosage can be increased to 2 mg once daily, if needed.
to the active substance or to any of the excipients, renal impairment requiring dialysis, intestinal perforation or obstruction due to structural or functional disorder of the gut wall, obstructive ileus, severe inflammatory conditions of the intestinal tract, such as Crohn’s disease, and ulcerative colitis
and toxic megacolon
/megarectum.
5-HT4 receptor
5-hydroxytryptamine receptor 4 is a protein that in humans is encoded by the HTR4 gene.- Location :The receptor is located in the alimentary tract, urinary bladder, heart and adrenal gland as well as the central nervous system ....
agonist
Agonist
An agonist is a chemical that binds to a receptor of a cell and triggers a response by that cell. Agonists often mimic the action of a naturally occurring substance...
which targets the impaired motility associated with chronic constipation
Constipation
Constipation refers to bowel movements that are infrequent or hard to pass. Constipation is a common cause of painful defecation...
, thus normalising bowel movements. Prucalopride was approved for use in Europe in 2009, but it has not been approved by the Food and Drug Administration
Food and Drug Administration
The Food and Drug Administration is an agency of the United States Department of Health and Human Services, one of the United States federal executive departments...
for use in the United States.
Mechanism of action
Prucalopride, a first in class dihydrobenzofurancarboxamide, is a selective, high affinity serotoninSerotonin
Serotonin or 5-hydroxytryptamine is a monoamine neurotransmitter. Biochemically derived from tryptophan, serotonin is primarily found in the gastrointestinal tract, platelets, and in the central nervous system of animals including humans...
(5-HT4
5-HT4 receptor
5-hydroxytryptamine receptor 4 is a protein that in humans is encoded by the HTR4 gene.- Location :The receptor is located in the alimentary tract, urinary bladder, heart and adrenal gland as well as the central nervous system ....
) receptor agonist with enterokinetic activities. Prucalopride alters colonic motility patterns via serotonin 5-HT4 receptor stimulation: it stimulates colonic mass movements, which provide the main propulsive force for defecation
Defecation
Defecation is the final act of digestion by which organisms eliminate solid, semisolid or liquid waste material from the digestive tract via the anus. Waves of muscular contraction known as peristalsis in the walls of the colon move fecal matter through the digestive tract towards the rectum...
.
The observed effects are exerted via highly selective action on 5-HT4 receptors: prucalopride has >150-fold higher affinity for 5-HT4 receptors than for other receptors. Prucalopride differs from other 5-HT4 agonists such as tegaserod
Tegaserod
Tegaserod is a 5-HT4 agonist manufactured by Novartis and sold under the name Zelnorm for the management of irritable bowel syndrome and constipation. Approved by the FDA in 2002, it was subsequently removed from the market in 2007 due to FDA concerns about possible adverse cardiovascular effects...
and cisapride
Cisapride
Cisapride is a gastroprokinetic agent, a drug which increases motility in the upper gastrointestinal tract. It acts directly as a serotonin 5-HT4 receptor agonist and indirectly as a parasympathomimetic. Stimulation of the serotonin receptors increases acetylcholine release in the enteric nervous...
, which at therapeutic concentrations also interact with other receptors (5-HT1B/D and the cardiac human ether-a-go-go K+ channel
HERG
hERG is a gene that codes for a protein known as Kv11.1 potassium ion channel...
respectively) and this may account for the adverse cardiovascular events that have resulted in the restricted availability of these drugs. Clinical trials evaluating the effect of prucalopride on QT interval and related adverse events have not demonstrated significant differences compared with placebo.
Pharmacokinetics
Prucalopride is rapidly absorbed (CmaxCMax
Cmax is a term used in pharmacokinetics refers to the maximum concentration that a drug achieves in tested area after the drug has been administrated and prior to the administration of a second dose...
attained 2–3 hours after single 2 mg oral dose) and is extensively distributed. Metabolism
Metabolism
Metabolism is the set of chemical reactions that happen in the cells of living organisms to sustain life. These processes allow organisms to grow and reproduce, maintain their structures, and respond to their environments. Metabolism is usually divided into two categories...
is not the major route of elimination. In vitro, human liver metabolism is very slow and only minor amounts of metabolite
Metabolite
Metabolites are the intermediates and products of metabolism. The term metabolite is usually restricted to small molecules. A primary metabolite is directly involved in normal growth, development, and reproduction. Alcohol is an example of a primary metabolite produced in large-scale by industrial...
s are found. A large fraction of the active substance is excreted unchanged (about 60% of the administered dose in urine
Urine
Urine is a typically sterile liquid by-product of the body that is secreted by the kidneys through a process called urination and excreted through the urethra. Cellular metabolism generates numerous by-products, many rich in nitrogen, that require elimination from the bloodstream...
and at least 6% in faeces). Renal excretion of unchanged prucalopride involves both passive filtration and active secretion. Plasma clearance averages 317 ml/min, terminal half-life is 24–30 hours, and steady-state is reached within 3–4 days. On once daily treatment with 2 mg prucalopride, steady-state plasma concentrations fluctuate between trough and peak values of 2.5 and 7 ng/ml, respectively.
In vitro data indicate that prucalopride has a low interaction potential, and therapeutic concentrations of prucalopride are not expected to affect the CYP-mediated metabolism of co-medicated medicinal products.
Efficacy
The primary measure of efficacy in the clinical trials is three or more spontaneous complete bowel movements per week; a secondary measure is an increase of at least one complete spontaneous bowel movement per week. Further measures are improvements in PAC-QOL (a quality of life measure) and PAC-SYM (a range of stoolHuman feces
Human feces , also known as a stool, is the waste product of the human digestive system including bacteria. It varies significantly in appearance, according to the state of the digestive system, diet and general health....
, abdominal, and rectal symptoms associated with chronic constipation). Infrequent bowel movements, bloating
Bloating
Bloating is any abnormal general swelling, or increase in diameter of the abdominal area. As a symptom, the patient feels a full and tight abdomen, which may cause abdominal pain sometimes accompanied by increased borborygmus or more seriously the total lack of borborygmus.-Symptoms:The most common...
, straining, abdominal pain
Abdominal pain
Abdominal pain can be one of the symptoms associated with transient disorders or serious disease. Making a definitive diagnosis of the cause of abdominal pain can be difficult, because many diseases can result in this symptom. Abdominal pain is a common problem...
, and defecation urge with inability to evacuate can be severe symptoms, significantly affecting quality of life.
In three large clinical trials, 12 weeks of treatment with prucalopride 2 and 4 mg/day resulted in a significantly higher proportion of patients reaching the primary efficacy endpoint of an average of ≥3 spontaneous complete bowel movements than with placebo
Placebo
A placebo is a simulated or otherwise medically ineffectual treatment for a disease or other medical condition intended to deceive the recipient...
. There was also significantly improved bowel habit and associated symptoms, patient satisfaction with bowel habit and treatment, and HR-QOL in patients with severe chronic constipation, including those who did not experience adequate relief with prior therapies (>80% of the trial participants). The improvement in patient satisfaction with bowel habit and treatment was maintained during treatment for up to 24 months; prucalopride therapy was generally well tolerated.
Side effects
Prucalopride has been given orally to ~2700 patients with chronic constipation in controlled clinical trials. The most frequently reported side effects are headacheHeadache
A headache or cephalalgia is pain anywhere in the region of the head or neck. It can be a symptom of a number of different conditions of the head and neck. The brain tissue itself is not sensitive to pain because it lacks pain receptors. Rather, the pain is caused by disturbance of the...
and gastrointestinal symptoms (abdominal pain, nausea
Nausea
Nausea , is a sensation of unease and discomfort in the upper stomach with an involuntary urge to vomit. It often, but not always, precedes vomiting...
or diarrhoea). Such reactions occur predominantly at the start of therapy and usually disappear within a few days with continued treatment.
Prescribing information
In the EEA, prucalopride is approved for the symptomatic treatmentSymptomatic treatment
Symptomatic treatment is any medical therapy of a disease that only affects its symptoms, not its cause, i.e., its etiology. It is usually aimed at reducing the signs and symptoms for the comfort and well-being of the patient, but it also may be useful in reducing organic consequences and sequelae...
of chronic constipation in women in whom laxatives fail to provide adequate relief. The recommended dosage in adults is 2 mg administered orally once daily; exceeding this dosage is not expected to increase efficacy. The recommended starting dose in elderly patients (>65 years) is 1 mg once daily; thereafter the dosage can be increased to 2 mg once daily, if needed.
Contraindications
Prucalopride is contraindicated where there is hypersensitivityHypersensitivity
Hypersensitivity refers to undesirable reactions produced by the normal immune system, including allergies and autoimmunity. These reactions may be damaging, uncomfortable, or occasionally fatal. Hypersensitivity reactions require a pre-sensitized state of the host. The four-group classification...
to the active substance or to any of the excipients, renal impairment requiring dialysis, intestinal perforation or obstruction due to structural or functional disorder of the gut wall, obstructive ileus, severe inflammatory conditions of the intestinal tract, such as Crohn’s disease, and ulcerative colitis
Ulcerative colitis
Ulcerative colitis is a form of inflammatory bowel disease . Ulcerative colitis is a form of colitis, a disease of the colon , that includes characteristic ulcers, or open sores. The main symptom of active disease is usually constant diarrhea mixed with blood, of gradual onset...
and toxic megacolon
Toxic megacolon
Toxic megacolon is an acute form of colonic distension. It is characterized by a very dilated colon , accompanied by abdominal distension , and sometimes fever, abdominal pain, or shock....
/megarectum.