Regulatory Decision Summary for Stromectol

Review decision

The Regulatory Decision Summary explains Health Canada’s decision for the product seeking market authorization. The Regulatory Decision Summary includes the purpose of the submission and the reason for the decision.


Product type:

Drug

Medicinal ingredient(s):

ivermectin

Therapeutic area:

Anthelmintics

Type of submission:

New Drug Submission

Control number:

211000
What was the purpose of this submission?

 

The purpose of this New Drug Submission (NDS) was to obtain market authorization for ivermectin 3 mg tablets in Canada for the treatment of intestinal strongyloidiasis, onchocerciasis and proven or suspected microfilaremia in patients with lymphatic filariasis caused by Wuchereria bancrofti. Currently ivermectin tablets are obtained in Canada through Health Canadas Special Access Program (SAP). Merck Canada has filed this NDS application to obtain market authorisation in Canada. Following assessment of the submitted evidence and discussion with the sponsor, Health Canada has approved ivermectin for the treatment of intestinal strongyloidiasis and onchocerciasis.

 

Why was the decision issued?

 

Ivermectin has been used for the treatment of intestinal strongyloidiasis and onchocerciasis for more than 30 years. It is considered as a primary choice in the treatment of these parasitic infections. The sponsor has provided five clinical studies including a study conducted in Zanzibar by the World Health Organization (WHO) to support the claim that a single 200ug/kg dose of ivermectin is effective in the treatment of intestinal strongyloidiasis. The efficacy of ivermectin in the treatment of onchocerciasis is supported by four pivotal studies and an additional study to support pediatric usage. Clinical studies demonstrate that ivermectin is better tolerated and with lesser clinical adverse effects as compared to alternate therapy available. In addition, it has the advantage of a single dose administration as compared to alternate drugs which require repeated administration.

Strongyloidiasis may be limited to the gastrointestinal tract but in immunocompromised patients disseminated disease occurs with the potential for autoinfection. This requires repeated treatment but the optimal dosing regimen is not known. In the treatment of onchocerciasis, ivermectin is very effective in decreasing microfilariae levels in the skin and in the anterior chamber of the eye but does not affect the viability of adult worms. As the lifespan of the adult worm is 8 to 10 years, and if the adult worms are not surgically excised, repeated follow-up and retreatment is required.

The safety of ivermectin in pregnancy is not established. Non-clinical studies indicate that ivermectin is teratogenic in rats, mice and rabbits. Limited post marketing surveillance has not established a relationship between exposure to ivermectin during the first trimester and the occurrence of adverse pregnancy outcomes. It is uncertain whether a single dose of ivermectin administered during the second and third trimesters would lead to pregnancy adverse outcomes. Its use in pregnant patients is limited to mass treatment programme where benefit to the mother exceeds the potential risk to the fetus. As mass treatment programme for onchocerciasis is not expected to be undertaken in Canada, ivermectin is not recommended for use during pregnancy.

The potential risk of loa loa encephalopathy during the treatment for strongyloidiasis or onchocerciasis with ivermectin in Canada is expected to be very rare. The Product Monograph includes appropriate Warnings and Precautions for pre-treatment assessment for loasis and careful post-treatment follow-up following ivermectin treatment.

Health Canada considers that the benefit/risk profile of Stromectol (ivermectin) is favourable for the treatment of patients with intestinal strongyloidiasis and onchocerciasis.

 

Decision issued

Approved; issued a Notice of Compliance in accordance with the Food and Drug Regulations.