HEQUINEL

What it is

Hequinel contains 200 mg hydroxychloroquine sulfate, which is equivalent to 155 mg base. The tablets are white to off-white, capsule-shaped, embossed "HCQS" on one side, plain on the other side. Hequinel tablets 200 mg are intended for oral administration.

Approved indications

— Rheumatoid arthritis — Mild systemic and discoid lupus erythematosus — Suppression and treatment of malaria

Dosing overview

Dosing varies by indication. For rheumatoid arthritis in adults, a suitable initial dosage is 400–600 mg daily, preferably taken at meal times. When a good response is obtained (usually in 4–12 weeks), the dose can be reduced to 200–400 mg daily (but should not exceed 6 mg/kg per day) and can be continued as maintenance treatment. For lupus erythematosus in adults, an initial dose of 400–800 mg daily is recommended, which can be maintained for several weeks and then reduced to a maintenance dose of 200–400 mg daily. For malaria suppression in adults, 400 mg (310 mg base) is taken on exactly the same day of each week. In children, the weekly suppressive dose is 5 mg (base) per kg bodyweight, but should not exceed the adult dose regardless of weight. For treatment of acute malarial attack in adults, an initial dose of 800 mg is followed by 400 mg 6–8 hours later and then 400 mg on each of two consecutive days (total dose of 2 g or 1.55 g base).

Key safety warnings

Cases of cardiomyopathy resulting in cardiac failure, in some cases with fatal outcome, have been reported in patients treated with hydroxychloroquine. Clinical monitoring for signs and symptoms of cardiomyopathy is advised and hydroxychloroquine should be discontinued if cardiomyopathy develops. Serious cases of drug-induced liver injury (DILI) including hepatocellular injury, acute hepatitis and fulminant hepatic failure (including fatal cases) have been reported during use of hydroxychloroquine. Irreversible retinal damage has been observed in some patients who had received long-term or high-dosage 4-aminoquinolone therapy for discoid and systemic lupus erythematosus or rheumatoid arthritis. Retinopathy has been reported to be dose related, and exceeding the recommended daily dose sharply increases the risk of retinal toxicity. Hydroxychloroquine has been shown to cause severe hypoglycaemia including loss of consciousness that could be life threatening in patients treated with and without anti-diabetic medications. Patients treated with hydroxychloroquine should be warned about the risk of hypoglycaemia and the associated clinical signs and symptoms. Hydroxychloroquine prolongs the QTc interval and should not be used in patients receiving drugs known to prolong the QT interval. Hydroxychloroquine should be used with caution in patients with congenital or documented acquired QT prolongation and/or known risk factors for prolongation of the QT interval such as cardiac disease, proarrhythmic conditions, a history of ventricular dysrhythmias, or uncorrected hypokalaemia and/or hypomagnesaemia. Cases of severe cutaneous adverse drug reactions (SCARs), including drug reaction with eosinophilia and systemic symptoms (DRESS), acute generalized exanthematous pustulosis (AGEP), Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN), have been reported during treatment with hydroxychloroquine. Patients with serious dermatological reactions may require hospitalization, as these conditions may be life-threatening and may be fatal.

Contraindications

Hydroxychloroquine is contraindicated in patients with pre-existing maculopathy of the eye, patients with known hypersensitivity to 4-aminoquinoline compounds, long-term therapy in children, and children under 6 years of age.

PBS listing

A tablet containing hydroxychloroquine sulfate 200 mg is listed on the PBS with 1 item, unrestricted restriction, and an ex-manufacturer price of A$13.08.

Regulatory history

Hequinel tablets 200 mg hydroxychloroquine sulfate was first registered on the ARTG on 2 February 2015.