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What is Strensiq® (asfotase alfa)?

Strensiq®: the first and only prescription medicine used to treat people with perinatal/infantile- and
juvenile-onset hypophosphatasia

If you or someone you love has been diagnosed with hypophosphatasia, you’re probably thinking a lot about what comes next. Now, you can take the next step in treating hypophosphatasia with Strensiq, a prescription medicine that works by replacing alkaline phosphatase.

Strensiq® can improve bone health in children with hypophosphatasia.

Baseline x-ray of child with hypophosphatasia whose bones are barely visible


X-ray of same child on treatment with Strensiq

What should I know about starting Strensiq®?


How can hypophosphatasia affect the bones and body?

Important Safety Information

What is Strensiq® (asfotase alfa)?

Strensiq is a prescription medicine used to treat people with perinatal/infantile- and juvenile-onset hypophosphatasia (HPP).

What are the possible side effects of Strensiq?

Strensiq may cause serious side effects, including

  • Serious allergic (hypersensitivity) reactions. Serious allergic reactions have happened in some people who use Strensiq. Stop using Strensiq and go to the nearest hospital emergency room right away if you have any of the signs and symptoms of a serious allergic reaction, including
    • Difficulty breathing
    • Swelling of your eyes, lips, or tongue
    • Hives
    • Feeling faint
    • Nausea or vomiting
    • Dizziness
    • Itching of your lips, tongue, or throat
    • Choking sensation
  • Skin thickening or pits at the injection site (lipodystrophy). Lipodystrophy at the injection site has happened several months after using Strensiq
  • Calcium buildup in your eyes and kidneys. Your healthcare provider should check your eyes and kidneys while you use Strensiq
The most common side effects of Strensiq include local skin injection-site reactions (including red skin patches, bruising, color change, pain, itching, thinning, swelling, pits, and bumps) and calcium buildup in your eyes and kidneys.

 Tell your doctor if you are pregnant or plan to become pregnant, or are breastfeeding or plan to breastfeed.

These are not all of the possible side effects of Strensiq. For more information, ask your healthcare provider or pharmacist. Call your healthcare provider for medical advice about side effects. You may report side effects to the US Food and Drug Administration at 1-800-FDA-1088.