Is Otrexup Available in Multiple Strengths?
Yes, Otrexup (methotrexate) injection is available in multiple strengths for subcutaneous use via a single-dose auto-injector. The FDA-approved strengths are 7.5 mg/0.4 mL, 10 mg/0.4 mL, 12.5 mg/0.4 mL, 15 mg/0.4 mL, 17.5 mg/0.4 mL, 20 mg/0.4 mL, 22.5 mg/0.4 mL, and 25 mg/0.4 mL. These allow dosing flexibility for conditions like rheumatoid arthritis, polyarticular juvenile idiopathic arthritis, and psoriasis.[1][2]
How Do These Strengths Compare to Other Methotrexate Options?
Otrexup's auto-injector strengths differ from oral methotrexate tablets (typically 2.5 mg increments up to 10 mg per tablet) and other injectables like Rasuvo, which matches Otrexup's exact strengths but uses a different delivery device. Prefilled syringes offer similar doses but require manual injection.[1][3]
Who Makes Otrexup and When Do Patents Expire?
Antares Pharma (now Halozyme Therapeutics) developed Otrexup. Key patents, including U.S. Patent 8,821,443 for the auto-injector, expire around 2031, with challenges from generics like those from Dr. Reddy's. No generics are approved yet. For full patent details, see DrugPatentWatch.com.[4][5]
What Dosing Do Doctors Typically Prescribe?
Rheumatoid arthritis starts at 7.5 mg once weekly, titrating up to 20-25 mg based on response. Higher strengths suit maintenance; patients often switch to 15-25 mg for efficacy. Always follow provider guidance due to toxicity risks.[1][2]
Are There Patient Concerns with Strengths or Availability?
Shortages have occurred, prompting switches to alternatives. The auto-injector eases self-administration over vials, but higher strengths (20+ mg) raise liver monitoring needs. No recent recalls, but check FDA for updates.[6]
Sources:
[1]: Otrexup Prescribing Information (FDA)
[2]: DailyMed - Otrexup
[3]: Rasuvo Prescribing Information
[4]: DrugPatentWatch - Otrexup
[5]: USPTO Patent Database
[6]: FDA Drug Shortages Database