Purple Book product · Reference 351(a)

Strensiq

asfotase alfa

351(a)BLA 125513RxLicensed Alexion Pharmaceuticals, Inc.

View asfotase alfa family Label PDF Open on FDA Purple Book

Oct 23, 2015

Approved

Reference 351(a)

License type

Marketing

None

Listed patents

Strensiq (asfotase alfa) is Alexion Pharmaceuticals, Inc.'s FDA-licensed reference biologic, approved under a 351(a) BLA in 2015. No biosimilars referencing Strensiq are listed in the Purple Book yet.

Sourced from the FDA Purple Book · verified Jul 02, 2026

Key dates

Approval
Approval date of this BLA submission.
Oct 23, 2015
10 yr 11 mo ago
Orphan exclusivity ends
7-year orphan-drug exclusivity window.
Oct 23, 2022
3 yr 9 mo ago
Today

Pharmaceutical detail

Strength

28MG/0.7ML

Dosage form

Injection

Route

Subcutaneous

Presentation

Single-Dose Vial

Center

CDER

License number

1743

Product number

002

Submission type

Original

Supplement number

Not listed

Change type

Not listed

Reference product family

View full family

This is the reference (originator) product. No biosimilars or interchangeables reference it in the Purple Book yet.

3 additional BLA records for this product (other strengths or presentations) are in the same reference family.

Patent list

No patent-list records were published for this product. The Purple Book patent list reflects the statutory patent exchange under the BPCIA and is not exhaustive.

Source provenance

Source kind · Advanced Search

Checked Jul 02, 2026

FDA source FDA source

advanced-searchAdvanced Search · Jul 02, 2026
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Change history

v4Jul 02, 2026
v3Jul 02, 2026
v2Jul 02, 2026

Frequently asked questions

Does Strensiq have approved biosimilars?

No 351(k) biosimilars or interchangeable biosimilars referencing Strensiq are listed in the FDA Purple Book yet.

What is Strensiq's BLA number?

Strensiq is licensed under BLA 125513, held by Alexion Pharmaceuticals, Inc..

When was Strensiq approved by the FDA?

Strensiq was approved by the FDA on Oct 23, 2015.

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