Palopag200 mg

Palopag is indicated for the treatment of pulmonary arterial hypertension (PAH, WHO Group I) to delay disease progression and reduce the risk of hospitalization for PAH.

• Established/approved use: Long-term treatment of PAH to slow worsening of disease and lower the risk of PAH-related hospitalization.
• Combination therapy: Palopag is commonly used as part of combination therapy with other PAH-specific medicines (e.g. endothelin receptor antagonists and/or phosphodiesterase-5 inhibitors), and clinical evidence for delaying disease progression is strongest when used in this combined approach; it may also be used as monotherapy in appropriate patients.
• Evidence base: Efficacy is supported by a large randomized controlled trial (event-driven, long-term outcome study) in patients with PAH, including idiopathic/heritable PAH and PAH associated with connective tissue disease.
• Palopag is not approved for and should not be used in other forms of pulmonary hypertension (e.g. pulmonary hypertension due to left heart disease, lung disease, or chronic thromboembolic disease) outside of WHO Group I PAH.

Each film-coated tablet contains Selexipag as the active pharmaceutical ingredient, available in a range of strengths used for the initial dose and step-wise dose titration (commonly supplied as a titration pack of ascending strengths for the initiation phase, followed by a fixed maintenance strength).

Tablets also contain standard pharmaceutical excipients (fillers, binders, and film-coating agents) that do not have independent pharmacological activity.

Palopag is an orally active, selective prostacyclin (IP) receptor agonist developed specifically for the long-term treatment of pulmonary arterial hypertension (PAH). Unlike prostacyclin analogues, Palopag and its active metabolite are chemically and pharmacologically distinct from prostacyclin, selectively targeting the IP receptor with a long duration of action that allows twice-daily oral dosing.

Palopag is metabolized to an active metabolite that is significantly more potent than the parent compound and is largely responsible for the drug's clinical effect. It is supplied as film-coated tablets and is typically initiated at a low dose and gradually titrated upward to the highest individually tolerated dose.

Palopag belongs to the therapeutic class of pulmonary arterial hypertension (PAH) therapies, specifically the prostacyclin (IP) receptor agonists — a non-prostanoid subclass distinct from prostacyclin analogues (e.g. epoprostenol, iloprost, treprostinil).

Mechanism of Action

Selexipag is a selective agonist of the prostacyclin IP receptor. Its active metabolite has substantially greater potency and a longer half-life than the parent drug, and is considered the primary mediator of clinical effect. Activation of the IP receptor produces vasodilation of pulmonary (and systemic) vasculature and has anti-proliferative effects on vascular smooth muscle cells, which together help delay the vascular remodeling and progressive right-heart strain seen in PAH.

Pharmacokinetics

• Absorption: Well absorbed orally; taking with food reduces the rate of absorption and improves gastrointestinal tolerability without materially reducing overall drug exposure.
• Metabolism: Hydrolyzed to an active metabolite, with further metabolism primarily via hepatic CYP2C8 (and, to a lesser extent, CYP3A4) and UGT enzymes.
• Elimination: Eliminated mainly via hepatic metabolism and biliary/fecal excretion, with a plasma half-life of the active metabolite that supports twice-daily dosing.

Palopag tablets are taken orally, twice daily approximately 12 hours apart, preferably with food to reduce nausea, headache, and other titration-related side effects. Tablets should be swallowed whole and not crushed, chewed, or split.

Clinically Significant Drug Interactions

• Strong CYP2C8 inhibitors (e.g. gemfibrozil): Substantially increase exposure to the active metabolite of Palopag. Start Palopag at 200 mcg once daily and do not exceed 800 mcg once daily when co-administered.
• Strong CYP2C8 inducers (e.g. rifampin): May significantly reduce exposure to Palopag's active metabolite, potentially reducing efficacy; monitor and adjust clinical management as needed.
• Other antihypertensive agents / vasodilators: Palopag can lower blood pressure; concomitant use with antihypertensives or other vasodilators may increase the risk of symptomatic hypotension — see Precautions and Warnings.
• Other PAH-specific therapies (endothelin receptor antagonists, PDE-5 inhibitors): No clinically significant pharmacokinetic interaction has been established; these are commonly co-administered as combination PAH therapy under specialist supervision.

Most adverse effects of Palopag are related to its mechanism as a prostacyclin-pathway (IP receptor) agonist and are typically most pronounced during dose initiation and titration, generally lessening once a stable maintenance dose is reached.

Very Common / Common

• Headache
• Diarrhea, nausea, vomiting
• Jaw pain
• Myalgia (muscle pain), arthralgia, pain in extremities
• Flushing
• Reduced appetite

Less Common but Notable

• Hypotension (see Precautions and Warnings)
• Anemia / decreased red blood cell counts
• Rash
• Hyperthyroidism (reported uncommonly)

Patients should be counseled that gradual, protocol-based up-titration reduces the severity of these class-related effects; symptoms that are severe or persistent should be reported to the prescribing physician.

Pregnancy: Data on the use of Palopag in pregnant women are limited. Pulmonary arterial hypertension itself carries substantial maternal and fetal risk, and pregnancy is generally discouraged in women with PAH. Palopag should be used during pregnancy only if clearly needed and if the potential benefit justifies the potential risk to the fetus, and only under close specialist supervision — consult a physician before use.

Lactation: It is not known whether Palopag or its active metabolite is present in human milk. Because of the potential for adverse effects in a breastfeeding infant, a decision should be made to discontinue breastfeeding or discontinue Palopag, taking into account the importance of treatment to the mother — consult a physician.

• Titration-related symptoms: Headache, diarrhea, nausea, jaw pain, flushing, and myalgia are common, especially during dose titration; these are class effects of prostacyclin-pathway stimulation. Gradual up-titration per protocol is recommended to improve tolerability.
• Hypotension: Palopag can lower blood pressure. Use with caution in patients also taking antihypertensive medicines or other drugs that lower blood pressure, and in patients with a history of significant hypotension, recent stroke, or recent myocardial infarction.
• Pulmonary veno-occlusive disease (PVOD): If signs of pulmonary edema develop during treatment, the possibility of underlying PVOD should be considered; Palopag should be discontinued if PVOD is confirmed.
• Do not stop abruptly: Abrupt discontinuation may lead to rebound worsening of PAH symptoms. Any change to therapy, including stopping Palopag, should be directed by the treating physician.
• Hepatic impairment: Requires dose adjustment in moderate impairment and is contraindicated in severe impairment (see Dosage and Contraindications).
• Specialist management: Palopag should be initiated and managed by a physician experienced in the diagnosis and treatment of PAH.
• Thyroid function: Hyperthyroidism has been reported uncommonly; new symptoms suggestive of thyroid dysfunction should be evaluated.

Overdose with Palopag may be expected to produce an exaggeration of its known pharmacological effects, including severe headache, nausea, vomiting, diarrhea, flushing, and hypotension. There is no specific antidote.

In case of suspected overdose, seek immediate medical attention or contact emergency services / a poison control center. Management should be supportive and symptomatic, with monitoring of vital signs (particularly blood pressure), under medical supervision; hemodialysis is not expected to be effective given the drug's protein binding and metabolism.

Store at room temperature (below 30°C), away from light and moisture, in the original packaging. Keep out of reach of children.

• Pediatric patients: Safety and efficacy of Palopag have not been established in patients under 18 years of age.
• Elderly (65 years and older): No overall clinically meaningful differences in safety or effectiveness have been observed compared to younger adults; no dedicated dose adjustment is required based on age alone, though age-related organ function should be considered.
• Hepatic impairment: Dose adjustment required in moderate impairment; contraindicated in severe impairment (see Dosage and Contraindications).
• Renal impairment: No dose adjustment generally required for mild-to-moderate impairment; limited data in severe renal impairment/end-stage renal disease — use with caution.

Palopag is intended for long-term, ongoing treatment of pulmonary arterial hypertension; it is not a short-course therapy. Duration of treatment should be determined and periodically reviewed by the treating specialist based on disease progression, functional status, and tolerability, with treatment typically continued indefinitely as part of chronic PAH management unless discontinued for medical reasons under physician guidance.

Selexipag is classified as a selective prostacyclin (IP) receptor agonist, a non-prostanoid subclass within pulmonary arterial hypertension (PAH) therapies, distinct from prostacyclin analogues, endothelin receptor antagonists, and PDE-5 inhibitors.

Selexipag selectively binds and activates the prostacyclin IP receptor. Its active metabolite (formed via hydrolysis and further hepatic metabolism) is substantially more potent and longer-acting than the parent compound and drives most of the pharmacological effect. IP receptor activation causes vasodilation of the pulmonary vasculature and exerts antiproliferative effects on vascular smooth muscle cells, helping counteract the vascular remodeling that drives progressive pulmonary arterial hypertension.

The safety and efficacy of Palopag in pediatric patients (under 18 years) have not been established. Palopag is not recommended for use in children outside of a specialist clinical trial setting.