Palynziq (pegvaliase-pqpz) is a medication by BioMarin for the treatment of phenylketonuria (PKU) in adults who have phenylalanine (Phe) blood levels above 600 micromoles/L with their current treatments.
How does Palynziq work?
Palynziq is designed to help lower the levels of Phe in the body. It is an enzyme replacement therapy that converts Phe into two other molecules, ammonia and trans-cinnamic acid.
How do I take it?
Palynziq is an under-the-skin injection. You will receive your first shot in a hospital setting where a medical professional can monitor you for at least an hour to make sure you are not having an allergic reaction to the treatment. After the initial injection, your doctor will show you or your caregiver how to use the preloaded syringes to administer the treatment at home.
How often should I take it?
You will receive Palynziq in three different phases where the treatment dose and frequency gradually increase. During the first four weeks, you will take 2.5 mg shots once a week. This is in the induction phase. After that, the weekly dose will double. Treatment will continue to ramp up during the titration phase until you reach the lowest daily dosage that achieves an effective reduction in Phe levels and that you can still tolerate. You will stay at this level during the maintenance phase. In the U.S., the maximum dose allowed was 40 mg per day but the U.S. Food and Drug Administration recently increased that limit to 60 mg per day.
Can I take Palynziq instead of staying on my diet?
Palynziq does not require patients to stay on a low-Phe diet. Most patients who took part in the Phase 3 clinical trial for Palynziq were not on a Phe-restricted diet and had an average intake of 1,700 mg of Phe per day. You should consult with your physician about the possible need to restart or continue a low-Phe diet to aid Palynziq in reducing your blood Phe levels, however, as the combination of the two might be more effective.
Does it work in all patients?
Palynziq may not work in all patients but 95 out of 118 patients (81%) who participated in the pivotal trial were able to achieve at least a 20% reduction in their Phe levels by 24 weeks of treatment.
What are the side effects?
The most serious possible side effect of Palynziq is a severe allergic reaction known as anaphylaxis. Symptoms of anaphylaxis include confusion, fainting, dizziness, trouble breathing, chest tightness, a fast heart rate, swelling of the face, throat tightness, rash, nausea, vomiting, diarrhea, loss of bladder and bowel control, and flushed skin. Your physician will train you to recognize the symptoms of anaphylaxis. If they happen, you should get an injection of epinephrine before seeking emergency assistance. Anaphylaxis can occur at any point during treatment so it is important to keep an epinephrine shot with you at all times.
The most common side effects include irritation at the injection site, joint pain, headache, nausea, stomach pain, itching, pain in the nose and throat, fatigue, diarrhea, and low levels of Phe in the blood.
Are there reasons I shouldn’t take Palynziq?
Researchers have not tested Palynziq in children or patients older than 65. If you are pregnant or may become pregnant, speak with your physician as Palynziq may cause harm to your baby.
How should I store it?
You should store Palynziq in the refrigerator between 36 F and 46 F (2 C to 8 C). Make sure you store it in its original container to protect it from light. You can store Palynziq out of the refrigerator at temperatures between 68 F and 77 F (20 C to 25 C) for up to 30 days. Do not put the syringes back in the refrigerator if you had kept them at room temperature.
Last updated: Dec. 3, 2020
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Phenylketonuria News is strictly a news and information website about the disease. It does not provide medical advice, diagnosis, or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.