Regulatory Decision Summary for Stoboclo

This New Drug Submission (NDS) was filed to obtain market authorization for Stoboclo (CT-P41, denosumab) as a biosimilar to Prolia (denosumab), the reference biologic drug in Canada, on the basis of comparative quality and clinical studies. All indications and clinical uses currently held by the authorized reference biologic in Canada, Prolia, are being sought.

The sponsor consented to information sharing between Health Canada and health technology assessment organizations as part of an aligned review pathway.

Comparative clinical pharmacokinetics/pharmacodynamics (PK/PD) between Stoboclo and Prolia were established in a single dose comparative study of Stoboclo (denosumab) and a United States (US)-sourced denosumab in healthy male participants. The US-sourced denosumab was used as a suitable proxy for the Canadian reference product. Evidence of comparable efficacy, safety and immunogenicity between Stoboclo and Prolia were also established in a multiple dose study of Stoboclo (denosumab) and a US-sourced denosumab, as a proxy for the Canadian reference product, in postmenopausal women with osteoporosis (PMO).

A scientific rationale was provided to support the authorization of Stoboclo for all indications held by the reference biologic drug. The rationale was based on the totality of evidence from analytical and functional characterization; the similarity in the pathophysiological disease progression of diseases treated by Prolia; and the mechanism of action of Prolia, which is similar across all authorized indications. No meaningful differences in PK/PD and the efficacy, safety and immunogenicity between Stoboclo and a US-sourced denosumab were observed.

The European Union Risk Management Plan (EU-RMP) and Canadian-specific Addendum submitted was reviewed and considered to be acceptable.

The chemistry and manufacturing information submitted for Stoboclo has demonstrated that the drug substance and drug product have been well characterized, are highly similar to the reference biological product (Prolia/Xgeva), and can be consistently manufactured to meet the approved specifications.

Following review and requested revisions, the final labelling and Product Monograph were considered to be acceptable.

Taken together, the benefit/risk profile is considered favorable for Stoboclo under the recommended condition of use. Therefore, a Notice of Compliance (NOC) was recommended.

For further details about Stoboclo, please refer to the Product Monograph, approved by Health Canada and available through the Drug Product Database.