Pegvaliase (Palynziq®) – Enzyme therapy for uncontrolled PKU
The US FDA has approved pegvaliase (Palynziq®, BioMarin Inc) for the treatment of phenylketonurea (PKU) uncontrolled by conventional therapy.
- Pegylated recombinant bacterial Anabaena variabilis phenylalanine ammonia lyase
- Subcutanous daily injection, 5-60 mg
- 51.1% decrease in blood Phe levels after 12 months of therapy
- Half of patients on treatment achieve blood Phe level < 120 µmol/L, the upper limit of normal range, within 2 years
- Adverse events (common): arthralgia (70.5%), injection-site reaction (62.1%), headache (47.1%)
- Adverse events (severe): anaphylaxis (4.6%)
- Current treatment: dietary phenylalanine restriction, sapropterin in THB-responsive PKU
The US FDA has approved the thrombopoietin receptor agonist avatrombopag (Doptelet®, AkaRx Inc) for the prevention of bleeding events in patients with chronic liver disease and thrombocytopenia undergoing a planned medical or dental procedure.
- Thrombopoietin receptor agonist, stimulates platelet production
- Decreases serious bleed risk 2-3 fold in patients w/ severe thrombocytopenia (<50*109/L) and chronic liver disease undergoing invasive procedures for up to 7 days after procedure
- Most common adverse events: fever, abdominal pain, fatigue, edema, nausea
- Current treatment: pre-procedural platelet transfusion
- May increase risk of thromboembolism in some patients
The US FDA has approved the cation chelator sodium zirconium cyclosilicate (ZS-9, Lokelma®) for the treatment of hyperkalemia.
Sodium Zirconium Cyclosilicate
- Oral potassium cation-exchange agent, not systemically absorbed
- Onset of action 1 hour, median 2.2 hours until normokalemic
- Not approved for life-threatening potassium elevations at this time
- Daily dosing for 1 year twice as likely as placebo to maintain normokalemia
- Most common adverse effects: GI distress, hypokalemia, UTI, edema
- Adverse effects less frequent than patiromer (alternative chelating agent for hyperkalemia)
The US FDA has approved the alpha-adrenergic agonist lofexidine HCl (Lucemyra®) for the treatment of opioid withdrawal symptoms.
- First non-opioid approved for treating opioid withdrawal symptoms
- Approved for up to 14 days after discontinuation of opioids
- Alpha-2 adrenergic agonist, suppresses sympathetic outflow
- Originally developed in 1980s for management of hypertension
- Most common side effects: hypotension, bradycardia, sedation and dizziness
- Alternative treatments for opioid withdrawal: gradual opioid dose taper, switch to less addictive opioids (e.g., methadone, buprenorphine), use opioid receptor antagonists (naltrexone)
The US FDA has approved the first antibody therapy, erenumab (Aimovig®) for the prevention of migraine headaches.
- Human monoclonal antibody
- Calcitonin-gene related peptide (CGRP) antagonist
- 1-2.5 fewer migraines/month
- Once-monthly self-injectable
- $6900/year before insurance and discounts
- Adverse effects: Injection site reactions and constipation
The US FDA has approved the first epoetin alfa biosimilar drug, Retacrit, (epoetin alfa – epbx) for the treatment of anemia.
- First biosimilar drug approved for epoetin alfa (Epogen/Procrit), a recombinant human erythropoetin
- Approved to treat anemia due to CKD, chemotherapy, zidovudine use, or surgical hemorrhage
- Epogen/Procrit currently accounts for significant % of Medicare spending, weekly treatments can cost $2,000
The US FDA has approved fingolimod (Gilenya by Novartis) for the treatment of multiple sclerosis (MS) in children aged 10 years or older.
- Once-daily, taken orally
- Inhibits lymphocyte migration to CNS (downregulates sphingosine receptor)
- Approved since 2010 for relapsing MS in adults
- Current first-line: Interferon beta/glatiramer acetate injections (off-label in pediatric MS)