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How can Strensiq® (asfotase alfa) help?

Watch the patient mobility video.

Strensiq® can improve bone health in people with perinatal/infantile-onset and juvenile-onset hypophosphatasia and has demonstrated other improvements, such as:

  • Improved survival in children with perinatal/infantile-onset hypophosphatasia
  • Improved growth, including height and weight, in people with perinatal/infantile- and juvenile-onset hypophosphatasia
Improved mobility and gait in children with juvenile-onset hypophosphatasia

Strensiq® improved survival in children with perinatal/infantile-onset hypophosphatasia.

Before treatment was available, less than half of infants with hypophosphatasia lived to their first birthday. During clinical trials, almost all children with perinatal/infantile-onset hypophosphatasia treated with Strensiq survived.

Strensiq® Patient Video
6-Minute Walk Test (6MWT)

(6MWT at baseline and 24 months)
  • The following table shows the 6MWT results for 1 patient with hypophosphatasia at baseline, 24 months, and 48 months as well as the study mean. The patient was 7 years, 3 months of age at study baseline and 9 years, 2 months of age at the 24-month (96-week) follow-up evaluation

Summary of Results

Baseline 24 Months 48 Months
Patient in Video 217 meters [age 7 years]
(41% of predicted normal distance)a
438 meters [age 9 years]
(76% of predicted normal distance)a
559 meters [age 11 years]
(91% of predicted normal distance)a
Study Mean (SD) n=8
343 meters
(41% of predicted normal distance)a
528 meters
(83% of predicted normal distance)a
588 meters
(89% of predicted normal distance)a

a6-minute walk test results were converted to mean percent-predicted values. Obtained values were expressed as a percentage of those observed in sex-, age-, and height-matched healthy children.

Step-by-step Strensiq® injection instructions.

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Learn how to inject Strensiq® (asfotase alfa)

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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 happened in some people who use STRENSIQ. Stop using STRENSIQ and go to the nearest hospital emergency room right away if you or your loved one 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) has happened several months after using STRENSIQ.
  • Calcium buildup in the eyes and kidneys can occur if you or your loved one have HPP. Your healthcare provider should check the eyes and kidneys while you or your loved one use STRENSIQ.
  • Decreased efficacy. Contact your healthcare provider if you or your loved one notice STRENSIQ is no longer working or experience worsening symptoms of HPP (e.g., increased respiratory support, increased difficulty walking, new fractures).
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.

Strensiq may affect other lab test results, therefore it is important that you present your Medical Alert Card to your healthcare team so they are aware that you are being treated with an alkaline phosphatase (ALP) replacement therapy which may cause incorrect results on certain laboratory tests.

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

These are not all 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.

Please see STRENSIQ full Prescribing Information, including Patient Information and Instructions for Use.

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