Strensiq: Uses, Dosage & Side Effects
A bone-targeted enzyme replacement therapy for the treatment of hypophosphatasia (HPP) with pediatric-onset disease
Strensiq (asfotase alfa) is a first-in-class bone-targeted enzyme replacement therapy approved for the treatment of hypophosphatasia (HPP), a rare and potentially life-threatening inherited metabolic disorder caused by deficient activity of the tissue-nonspecific alkaline phosphatase (TNSALP) enzyme. By replacing the missing enzyme, Strensiq enables proper skeletal mineralization, improves bone growth and strength, and addresses the underlying cause of HPP rather than merely managing symptoms. It is administered as a subcutaneous injection, typically six times or three times per week, with dosing based on body weight. Strensiq has demonstrated significant improvements in skeletal mineralization, respiratory function, growth, and survival in clinical studies, and has received orphan drug designation in both the EU and the US.
Quick Facts: Strensiq
Key Takeaways
- Strensiq (asfotase alfa) is the first and only approved enzyme replacement therapy for hypophosphatasia (HPP), a rare genetic disorder that impairs bone mineralization due to deficient tissue-nonspecific alkaline phosphatase (TNSALP) activity.
- The standard dose is 6 mg/kg per week given as subcutaneous injections, either 1 mg/kg six times weekly or 2 mg/kg three times weekly, with the dose adjusted as body weight changes.
- Clinical studies have demonstrated significant improvements in skeletal mineralization, bone growth, respiratory function, and overall survival, particularly in infants and children with severe HPP.
- The most common side effects are injection site reactions (redness, pain, swelling, lipodystrophy), fever, and irritability; serious anaphylaxis-like allergic reactions have also been reported.
- Strensiq must be stored refrigerated (2–8 °C) and used within 3 hours of removal from the refrigerator; each vial is for single use only and should not be frozen.
What Is Strensiq and What Is It Used For?
Strensiq contains the active substance asfotase alfa, a human recombinant tissue-nonspecific alkaline phosphatase (TNSALP) fusion protein. It is produced using recombinant DNA technology in Chinese hamster ovary (CHO) cells and is specifically engineered to target bone tissue. The molecule consists of the catalytic domain of human TNSALP fused to an Fc fragment of human immunoglobulin G1 (IgG1) and a deca-aspartate bone-targeting domain. This unique design allows asfotase alfa to bind to hydroxyapatite crystals in bone, delivering enzymatic activity precisely where it is most needed for skeletal mineralization.
Understanding Hypophosphatasia (HPP)
Hypophosphatasia (HPP) is a rare, inherited metabolic disorder caused by loss-of-function mutations in the ALPL gene, which encodes the tissue-nonspecific alkaline phosphatase (TNSALP) enzyme. This enzyme plays a critical role in bone mineralization by hydrolyzing inorganic pyrophosphate (PPi), a potent inhibitor of hydroxyapatite crystal formation. When TNSALP activity is deficient, PPi accumulates in the body and prevents calcium and phosphate from being deposited properly into the bone matrix, leading to defective mineralization of the skeleton and teeth.
HPP has a wide spectrum of clinical severity, ranging from perinatal lethal forms with almost no skeletal mineralization to mild adult forms with stress fractures and dental abnormalities. The classification of HPP is based on age of onset and clinical severity:
- Perinatal severe HPP: The most severe form, presenting at birth or in utero with profound skeletal undermineralization, shortened and deformed limbs, respiratory insufficiency, and often fatal outcomes without treatment.
- Infantile HPP: Onset before 6 months of age with failure to thrive, rickets-like skeletal deformities, hypercalcemia, respiratory compromise, and risk of vitamin B6-dependent seizures.
- Childhood HPP: Onset after 6 months with premature loss of deciduous teeth (baby teeth with intact roots), skeletal deformities, short stature, bone pain, difficulty walking, and fractures.
- Adult HPP: Characterized by recurrent stress fractures (particularly metatarsal), early loss of permanent teeth, chronic musculoskeletal pain, and reduced mobility.
- Odontohypophosphatasia: The mildest form, affecting only the teeth with premature loss and dental abnormalities.
HPP is estimated to affect approximately 1 in 100,000 to 1 in 300,000 live births for the severe forms, although milder forms may be more prevalent and underdiagnosed. The disease is caused by autosomal recessive inheritance in severe forms and can be autosomal dominant in milder adult-onset cases. More than 400 different mutations in the ALPL gene have been identified to date, contributing to the wide phenotypic variability of the disease.
How Strensiq Works
Asfotase alfa works by replacing the deficient TNSALP enzyme in patients with HPP. Once administered subcutaneously, the fusion protein enters the bloodstream and is specifically directed to bone tissue by its deca-aspartate domain, which has high affinity for hydroxyapatite crystals in the bone matrix. At the bone surface, asfotase alfa catalyzes the hydrolysis of accumulated inorganic pyrophosphate (PPi) into inorganic phosphate (Pi), thereby removing the mineralization inhibitor and restoring the normal process of hydroxyapatite crystal deposition in bone.
In addition to hydrolyzing PPi, asfotase alfa also metabolizes pyridoxal 5'-phosphate (PLP), the circulating form of vitamin B6 that accumulates when TNSALP is deficient. Elevated PLP levels are a hallmark biomarker of HPP and can contribute to vitamin B6-dependent seizures, particularly in the perinatal and infantile forms of the disease. By normalizing PLP levels, Strensiq helps to reduce the risk of these potentially fatal seizures.
Clinical Evidence
Strensiq was evaluated in several clinical studies involving patients with pediatric-onset HPP. Due to the rarity of the disease, these studies were open-label, single-arm trials compared with historical control groups. The pivotal studies demonstrated:
- Improved skeletal mineralization: Radiographic assessments using the Radiographic Global Impression of Change (RGI-C) scale showed significant improvement in skeletal mineralization within the first 24 weeks of treatment, with continued improvement over several years of therapy.
- Improved survival: In a study of infants and young children with life-threatening HPP, treatment with Strensiq resulted in a survival rate of 84% at age 5, compared with 27% in a matched historical control group who did not receive the treatment.
- Improved growth: Height Z-scores improved significantly over the course of treatment, indicating normalization of growth in children with HPP.
- Improved respiratory function: Many patients who previously required respiratory support (including mechanical ventilation) showed sufficient improvement to be weaned off ventilatory support.
Strensiq was first approved by the EMA in August 2015 under exceptional circumstances (due to the rarity of HPP making it impossible to obtain complete data) and by the FDA in October 2015. It is now approved in more than 30 countries worldwide and has received orphan drug designation in both the EU and US, reflecting its importance as the only targeted treatment for this rare disease.
Because hypophosphatasia is an ultra-rare disease, it was not possible to conduct large-scale randomized controlled trials. Strensiq was approved based on open-label studies with historical control comparisons. The European Medicines Agency reviews new information on the medicine annually and updates the product information as needed.
What Should You Know Before Taking Strensiq?
Contraindications
The primary contraindication to Strensiq use is severe hypersensitivity (allergy) to asfotase alfa or to any of the other ingredients in the formulation. The excipients include sodium chloride, monobasic sodium phosphate monohydrate, dibasic sodium phosphate heptahydrate, and water for injections. If you have experienced a severe allergic reaction to any of these components in the past, you must not use Strensiq.
It is important to distinguish between severe allergic reactions (which are a contraindication) and mild injection site reactions (which are very common and do not necessarily preclude continued treatment). Your healthcare provider will assess whether any reactions you experience require discontinuation of therapy or whether treatment can be continued under close medical supervision.
Warnings and Precautions
Life-threatening allergic reactions resembling anaphylaxis have been reported with Strensiq. Symptoms may include difficulty breathing, choking sensation, nausea, swelling around the eyes, and dizziness. These reactions can occur within minutes after injection and may happen even in patients who have been receiving the drug for more than one year. If you experience any of these symptoms, stop using Strensiq immediately and seek emergency medical care.
Before and during treatment with Strensiq, discuss the following with your healthcare provider:
- Anaphylaxis-like reactions: Patients have experienced life-threatening allergic reactions requiring emergency medical treatment. These reactions occurred within minutes of injection and have been reported in patients who had been using Strensiq for over a year. If you experience such a reaction, your doctor will discuss whether to re-initiate treatment under medical supervision.
- Anti-drug antibodies: Your body may develop antibodies against asfotase alfa during treatment. This is a known phenomenon with biologic therapies and may potentially reduce the effectiveness of treatment over time. Inform your doctor if you feel that Strensiq is becoming less effective.
- Injection site lipodystrophy: Fatty lumps or loss of fat tissue beneath the skin at injection sites have been reported after several months of regular injections. To minimize this risk, it is essential to rotate injection sites systematically between the abdomen, thigh, and upper arm.
- Eye-related side effects: Calcium deposits in the eye (conjunctival and corneal calcification) have been reported in studies, both in patients treated with Strensiq and in untreated patients with HPP. This appears to be related to the underlying disease rather than the treatment, but you should report any vision problems to your doctor promptly.
- Craniosynostosis: Premature fusion of skull bones has been reported in clinical studies of infants and young children under 5 years with HPP, both with and without Strensiq treatment. Parents and caregivers should report any changes in the shape of the child's head to the treating physician.
- Parathyroid hormone and calcium levels: Increased parathyroid hormone levels and low blood calcium (hypocalcemia) have been reported during treatment. Your doctor may prescribe calcium and vitamin D supplements if needed.
- Weight gain: Weight gain may occur during Strensiq treatment, likely reflecting improved nutritional status and growth. Your doctor can provide dietary guidance as needed.
Pregnancy and Breastfeeding
Strensiq should not be used during pregnancy unless clearly necessary, as the effects of asfotase alfa on human pregnancy have not been adequately studied. Women of childbearing potential should consider using effective contraception during treatment. If you become pregnant or suspect you are pregnant while receiving Strensiq, inform your doctor immediately. The decision about whether to continue, discontinue, or initiate treatment during pregnancy should be made on a case-by-case basis, considering the severity of the underlying HPP and the potential risks and benefits.
It is not known whether asfotase alfa is excreted in human breast milk. The decision to breastfeed during Strensiq treatment should be made in consultation with your doctor, weighing the benefits of breastfeeding for the child against the benefits of continued Strensiq treatment for the mother. Given that HPP is typically a chronic, life-long condition requiring ongoing enzyme replacement, interruption of treatment carries its own risks that must be considered.
Driving and Operating Machinery
Strensiq is not expected to affect your ability to drive or operate machinery. No studies on the effects of asfotase alfa on driving ability have been performed, but based on the known pharmacological properties and side effect profile, impairment is unlikely.
Interference with Laboratory Tests
If you need to undergo laboratory tests (blood tests), inform your healthcare provider that you are being treated with Strensiq. Asfotase alfa can interfere with certain laboratory assays, particularly those that measure alkaline phosphatase activity. This can lead to falsely elevated or reduced results for some tests. Your laboratory may need to use alternative testing methods to ensure accurate results while you are on Strensiq therapy.
Important Information About Ingredients
Strensiq contains less than 1 mmol (23 mg) of sodium per vial, meaning it is essentially sodium-free. This is relevant for patients who are on a sodium-restricted diet. The solution also contains sodium chloride, monobasic sodium phosphate monohydrate, dibasic sodium phosphate heptahydrate, and water for injections.
How Does Strensiq Interact with Other Drugs?
Because asfotase alfa is a large biologic protein rather than a small-molecule drug, it is degraded through general protein catabolic pathways (similar to endogenous immunoglobulins) rather than being metabolized by hepatic cytochrome P450 enzymes. This means that traditional pharmacokinetic drug-drug interactions, which typically involve competition for or inhibition of metabolic enzymes, are not expected with Strensiq.
No formal drug interaction studies have been performed with asfotase alfa. In clinical trials, patients receiving Strensiq were allowed to continue their existing medications, and no clinically significant interactions were identified. Given the severe and life-threatening nature of HPP, particularly in its infantile and perinatal forms, patients often receive concomitant therapies including:
| Drug Category | Examples | Interaction Status |
|---|---|---|
| Calcium supplements | Calcium carbonate, calcium citrate | No interaction identified; often co-prescribed |
| Vitamin D supplements | Cholecalciferol, alfacalcidol | No interaction identified; often co-prescribed |
| Analgesics | Paracetamol, NSAIDs, opioids | No interaction identified |
| Anticonvulsants | Pyridoxine (vitamin B6), levetiracetam | No interaction identified |
| Respiratory medications | Bronchodilators, inhaled corticosteroids | No interaction identified |
| Bisphosphonates | Alendronate, zoledronic acid | Potential concern: PPi analog; discuss with doctor |
While no formal pharmacokinetic interactions are expected, one theoretical pharmacodynamic consideration deserves mention. Bisphosphonates are structural analogs of pyrophosphate (PPi) and act by inhibiting bone resorption. Since the mechanism of HPP involves accumulation of PPi that inhibits bone mineralization, and since Strensiq works by hydrolyzing PPi, the combined use of Strensiq and bisphosphonates has not been well-studied and should be discussed with a specialist. In general, bisphosphonates are avoided in HPP patients because they may worsen the underlying mineralization defect.
As mentioned previously, Strensiq can interfere with certain laboratory assays that use alkaline phosphatase as a reagent or measure alkaline phosphatase activity. If you are scheduled for blood tests, always inform the laboratory staff that you are receiving Strensiq so that appropriate testing methods can be used.
Strensiq may cause falsely elevated or reduced results in laboratory tests that rely on alkaline phosphatase measurements. Always inform your doctor and laboratory that you are receiving enzyme replacement therapy with asfotase alfa before having blood tests. Alternative assay methods may be needed for accurate results.
What Is the Correct Dosage of Strensiq?
Strensiq should always be used exactly as prescribed by your doctor. Treatment should be initiated by a physician experienced in the management of metabolic or skeletal diseases. After initial training from a healthcare professional, patients or caregivers can administer Strensiq injections at home. The dosing regimen is weight-based and consistent across all age groups.
Standard Dosing Regimen
The total weekly dose of Strensiq is 6 mg of asfotase alfa per kilogram of body weight. This total weekly dose can be divided according to one of two schedules:
| Schedule | Dose per Injection | Frequency | Total Weekly Dose |
|---|---|---|---|
| 3x Weekly | 2 mg/kg | 3 times per week | 6 mg/kg |
| 6x Weekly | 1 mg/kg | 6 times per week | 6 mg/kg |
Your doctor will determine which schedule is most appropriate based on your clinical situation, lifestyle, and practical considerations. Some patients may benefit from the six-times-weekly schedule (smaller individual injection volumes, which may be easier for very young children), while others may prefer the three-times-weekly schedule for convenience.
The concentration of Strensiq is 40 mg/mL. The exact volume to inject for each dose depends on the patient's body weight and the chosen schedule. Strensiq is available in four vial sizes:
- 0.3 mL vial (12 mg asfotase alfa) – dark blue color code
- 0.45 mL vial (18 mg asfotase alfa) – orange color code
- 0.7 mL vial (28 mg asfotase alfa) – light blue/pink color code
- 1 mL vial (40 mg asfotase alfa) – green color code
The maximum volume per single injection is 1 mL. If the calculated dose requires more than 1 mL, multiple injections must be given at different injection sites during the same administration session. Your doctor will adjust the dose periodically as your body weight changes, which is particularly important in growing children.
Injection Sites and Technique
Strensiq is administered as a subcutaneous injection. Suitable injection sites include:
- Abdomen (belly area): Choose areas with adequate subcutaneous fat.
- Thighs: The front or outer part of the thigh.
- Upper arms: The outer part of the upper arm (may require assistance from a caregiver).
- Buttocks: Areas with sufficient subcutaneous tissue.
It is essential to rotate injection sites regularly to minimize the risk of injection site reactions and lipodystrophy. Do not inject into areas that are lumpy, hard, or painful. If you notice any changes in the skin or tissue at injection sites, inform your healthcare provider promptly.
Missed Dose
If you miss a scheduled injection, do not inject a double dose to compensate. Contact your healthcare provider for guidance on how to resume your regular dosing schedule. Consistent adherence to the prescribed injection schedule is important for maintaining optimal enzyme levels and therapeutic benefit.
Overdose
If you suspect that you have accidentally received a higher dose of Strensiq than prescribed, contact your doctor or healthcare provider for advice immediately. There is no specific antidote for asfotase alfa overdose. Treatment would be supportive, focusing on monitoring and management of any symptoms.
Strensiq can be self-injected at home after you or your caregiver have received proper training from a healthcare professional. Always inspect the solution before injection: it should be clear, slightly opalescent, colorless to slightly yellow, and may contain a few small translucent or white particles. Do not use the solution if it is discolored, cloudy, or contains large particles. Each vial is for single use only and should be discarded after use.
What Are the Side Effects of Strensiq?
Like all medicines, Strensiq can cause side effects, although not everybody gets them. The side effects vary in frequency and severity. The most clinically significant adverse reactions are serious allergic reactions and injection site reactions. Below is a comprehensive summary of reported side effects organized by frequency.
The most serious side effect reported with Strensiq is life-threatening allergic reactions resembling anaphylaxis (common: affects up to 1 in 10 patients). Symptoms include difficulty breathing, choking sensation, nausea, swelling around the eyes, and dizziness. These reactions occurred within minutes of injection and have been reported even after more than one year of treatment. If you experience any of these symptoms, stop using Strensiq immediately and seek emergency medical attention.
Other hypersensitivity reactions have also been reported, including flushing (erythema), fever, rash, itching (pruritus), irritability, nausea, vomiting, pain, chills, numbness of the mouth (oral hypoesthesia), headache, facial flushing, rapid heart rate (tachycardia), and cough. If you experience any of these symptoms, stop using Strensiq and seek medical attention immediately.
Very Common
May affect more than 1 in 10 people
- Injection site reactions (redness, discoloration, itching, pain, fatty lumps or loss of fatty tissue [lipodystrophy], lighter skin area [hypopigmentation], and/or swelling)
- Fever (pyrexia)
- Irritability
- Skin redness (erythema)
- Pain in hands and feet (pain in extremities)
- Bruising (contusion)
- Headache
Common
May affect up to 1 in 10 people
- Anaphylaxis-like allergic reactions
- Stretched or tight skin, skin discoloration
- Nausea
- Numbness of the mouth (oral hypoesthesia)
- Muscle pain (myalgia)
- Scarring at injection sites
- Increased tendency to bruise
- Hot flush
- Skin infection at injection site (injection site cellulitis)
- Low calcium levels in the blood (hypocalcemia)
- Kidney stones (nephrolithiasis)
Additional considerations regarding the side effect profile of Strensiq include:
- Injection site lipodystrophy: Localized loss or accumulation of fat at injection sites has been reported with long-term use. This underscores the importance of rotating injection sites consistently between the abdomen, thighs, upper arms, and buttocks.
- Ectopic calcification: Eye calcifications (conjunctival and corneal) have been reported, but these appear to be related to the underlying HPP rather than to Strensiq treatment itself. Regular ophthalmologic monitoring may be recommended by your doctor.
- Craniosynostosis: Premature fusion of skull bones has been observed in infants under 5 years, both in treated and untreated HPP patients. It remains unclear whether this is a consequence of improved bone mineralization with treatment or part of the natural disease course.
- Hypocalcemia: Low blood calcium and elevated parathyroid hormone levels have been reported. Your doctor may monitor calcium levels and prescribe calcium and vitamin D supplementation as needed.
It is important to report any suspected side effects to your healthcare provider or national pharmacovigilance authority. Reporting helps to continuously monitor the benefit-risk balance of Strensiq, which is especially important for orphan drugs where clinical experience is inherently limited.
How Should You Store Strensiq?
Proper storage of Strensiq is essential to maintain its efficacy and safety. As a biologic protein, asfotase alfa is sensitive to temperature extremes and light exposure. Follow these storage guidelines carefully:
- Refrigeration: Store unopened vials in a refrigerator at 2–8 °C (36–46 °F). This is the standard temperature range for most household refrigerators.
- Do not freeze: Freezing can damage the protein structure of asfotase alfa and render it ineffective. If a vial has been accidentally frozen, it should be discarded.
- Protect from light: Keep vials in the original carton to protect from light exposure until ready for use.
- Room temperature use: Remove the vial from the refrigerator 15 to 30 minutes before injection to allow it to reach room temperature. Do not warm by any other means (e.g., microwave or hot water). Once removed from the refrigerator, use within a maximum of 3 hours at room temperature (23–27 °C).
- Single use only: Each vial is intended for one-time use. Do not re-enter a vial that has already been punctured. Discard any unused solution after injection.
- Expiration date: Do not use the medication after the expiration date printed on the carton and vial label. The expiration date refers to the last day of that month.
- Disposal: Do not dispose of medicines through household waste or wastewater. Ask your pharmacist how to dispose of unused medicines safely to protect the environment.
Keep Strensiq out of the sight and reach of children. If you have questions about proper storage, consult your pharmacist or healthcare provider.
What Does Strensiq Contain?
Strensiq is supplied as a clear, slightly opalescent, colorless to slightly yellow aqueous solution for subcutaneous injection. Some small translucent or white particles may be present, which is normal and does not affect the quality of the medicine.
| Vial Volume | Asfotase Alfa Content | Concentration | Pack Sizes |
|---|---|---|---|
| 0.3 mL | 12 mg | 40 mg/mL | 1 or 12 vials |
| 0.45 mL | 18 mg | 40 mg/mL | 1 or 12 vials |
| 0.7 mL | 28 mg | 40 mg/mL | 1 or 12 vials |
| 1 mL | 40 mg | 40 mg/mL | 1 or 12 vials |
The inactive ingredients (excipients) in Strensiq are:
- Sodium chloride
- Monobasic sodium phosphate monohydrate
- Dibasic sodium phosphate heptahydrate
- Water for injections
The marketing authorization holder is Alexion Europe SAS (part of AstraZeneca Rare Disease), based in Levallois-Perret, France. Manufacturing is performed by Alexion Pharma International Operations Limited in Dublin, Ireland. Not all pack sizes may be marketed in all countries.
Frequently Asked Questions About Strensiq
Hypophosphatasia (HPP) is a rare inherited metabolic disorder caused by mutations in the ALPL gene, leading to deficient activity of the tissue-nonspecific alkaline phosphatase (TNSALP) enzyme. This enzyme is essential for proper mineralization of bones and teeth. Without adequate TNSALP activity, a substance called inorganic pyrophosphate (PPi) accumulates and prevents calcium and phosphate from being deposited into bone. This results in soft, weak bones that are prone to fractures and deformities, as well as premature tooth loss, respiratory problems, and in severe cases, seizures. Strensiq replaces the missing enzyme and is the only approved targeted treatment for HPP.
Strensiq is intended as a long-term enzyme replacement therapy. Since HPP is a genetic condition caused by a permanent deficiency of the TNSALP enzyme, treatment with Strensiq typically continues indefinitely to maintain its beneficial effects on bone mineralization, growth, and other aspects of the disease. Discontinuation of therapy may lead to a recurrence of symptoms and worsening of skeletal mineralization. Your doctor will monitor your response to treatment regularly and discuss the ongoing need for therapy with you.
Strensiq injections are typically administered by a parent or caregiver for infants and young children. Older children and adolescents may be trained to self-inject under the supervision of a healthcare professional, depending on their maturity and ability to follow the injection technique correctly. The initial training should always be provided by a qualified healthcare professional, and the first few self-injections should be performed under supervision to ensure proper technique. Your treating physician will advise on the appropriate age and readiness for self-injection.
If you experience symptoms of a severe allergic reaction after a Strensiq injection — such as difficulty breathing, choking sensation, swelling around the eyes, severe dizziness, or nausea — stop using Strensiq immediately and seek emergency medical care. After the reaction has been evaluated and treated, your doctor will discuss with you the appropriate next steps, including whether it is safe to resume Strensiq treatment under medical supervision. Mild injection site reactions (redness, mild pain, swelling) are very common and usually do not require discontinuation of treatment.
Strensiq has received regulatory approval in numerous countries including the EU member states, the United States, Japan, Canada, and several other countries. However, availability and reimbursement may vary by country. As an orphan drug for an ultra-rare disease, access programs and compassionate use arrangements may be available in countries where Strensiq has not yet received formal marketing authorization. Your doctor or a patient advocacy organization for rare diseases can help you determine availability in your specific country.
The dose of Strensiq is calculated based on body weight. The recommended total weekly dose is 6 mg per kilogram of body weight. This can be given as 2 mg/kg three times per week or 1 mg/kg six times per week. Your doctor will determine the appropriate injection volume and vial size based on your weight and will adjust the dose periodically as your weight changes, which is particularly important for growing children. The maximum volume per single injection is 1 mL; if the dose requires more, multiple injections at different sites are given.
References
- European Medicines Agency (EMA). Strensiq (asfotase alfa) – Summary of Product Characteristics. Last updated 2025. Available at: ema.europa.eu
- U.S. Food and Drug Administration (FDA). Strensiq (asfotase alfa) Prescribing Information. Alexion Pharmaceuticals, Inc. Revised 2024.
- Whyte MP, et al. Asfotase alfa treatment improves survival for perinatal and infantile hypophosphatasia. J Clin Endocrinol Metab. 2016;101(1):334-342. doi:10.1210/jc.2015-3462
- Whyte MP, et al. Hypophosphatasia – aetiology, nosology, pathogenesis, diagnosis and treatment. Nat Rev Endocrinol. 2016;12(4):233-246. doi:10.1038/nrendo.2016.14
- Kishnani PS, et al. Five-year efficacy and safety of asfotase alfa therapy for adults and adolescents with hypophosphatasia. Bone. 2019;121:149-162. doi:10.1016/j.bone.2019.01.021
- Hofmann CE, et al. Efficacy and safety of asfotase alfa in infants and young children with hypophosphatasia: a phase 2 open-label study. J Clin Endocrinol Metab. 2019;104(7):2735-2747. doi:10.1210/jc.2018-02335
- World Health Organization (WHO). Model List of Essential Medicines – 23rd List (2023). Available at: who.int
- Mornet E. Hypophosphatasia. Orphanet Journal of Rare Diseases. 2007;2:40. doi:10.1186/1750-1172-2-40
- Bishop N, et al. European Society for Paediatric Endocrinology (ESPE) clinical practice guidelines for the management of hypophosphatasia. 2024.
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