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interferon [IFN]-beta 1B (betaseron, Extavia)

Tradename: Betaseron. Recombinant protein. Indications: 1) multiple sclerosis 2) hepatitis C Contraindications: 1) hypersensitivity to albumin 2) hypersensitivity to E. coli-derived products 3) NOT recommended for patients < 18 years of age 4) not recommended for patients with liver disease Pregnancy category: C [1] Dosage: 0.25 mg (8 million units) SC/IM every other day Powder for injection: 0.3 mg (9.6 million units) single use only Autoinjector Betaconnect available in early 2016 [7] Pharmacokinetics: 1) bioavailability 50% 2) elimination 1/2life of 8 minutes - 4.3 hours Monitor: - complete blood count (CBC) [1] - liver function testings at 1, 3, & 6 month, then periodically & as clinically indicated [6]; - Canadian guidelines recommend LFTs at baseline, monthly for 6 months, then every 6 months Adverse effects: 1) common (> 10%) - flu-like symptoms decline after 4-6 weeks of therapy [1] - fever - malaise - myalgias - fatigue [1] - injection site inflammation - development of antibodies with loss of clinical efficacy with chronic therapy B2) less common (1-10%) - tachycardia, syncope, headache, lethargy, depression, emotional lability, anxiety, suicidal ideation, somnolence, agitation, confusion, hypocalcemia, spasticity, nausea/vomiting, anorexia, diarrhea, chronic weight loss, leukopenia, thrombocytopenia, anemia (mild, dose-related), weakness, retinal toxicity, visual changes, elevated liver function tests (mild & transient), renal insufficiency (elevated BUN & serum creatinine) 3) uncommon (< 1%) - CHF, alopecia, autoimmune hepatitis 4) other - menstrual problems - photosensitivity ?, sunblock recommended - bone marrow fibrosis ? Drug interactions: - decreased clearance/increased toxicity of zidovudine Laboratory: - interferon beta 1b Ab in serum/plasma Mechanism of action: - reduces frequency of relapse & new brain lesions visualized by MRI - neutralizing antibodies IFN-beta are produced diminishing clinical effectiveness [6]

Related

IFN-alpha 2b/ribavirin (Rebetron)

General

biological response modifier; immune factor; immunomodulator; biomodulator neurologic agent recombinant protein; chimer interferon beta; IFN-beta; fibroblast interferon (IFNB1, IFB, IFNB) pharmaceutical interferon

References

  1. Medical Knowledge Self Assessment Program (MKSAP) 11, 17, 18. American College of Physicians, Philadelphia 1998, 2015, 2018
  2. Kaiser Permanente Northern California Regional Drug Formulary, 1998
  3. Drug Information & Medication Formulary, Veterans Affairs, Central California Health Care System, 1st ed., Ravnan et al eds, 1998
  4. Geriatric Dosage Handbook, 6th edition, Selma et al eds, Lexi-Comp, Cleveland, 2001
  5. Department of Veterans Affairs, VA National Formulary
  6. Prescriber's Letter 17(7): 2010 Recommended Lab Monitoring for Common Medications Liver Function Test Scheduling Detail-Document#: 260704 (subscription needed) http://www.prescribersletter.com
  7. Bayer News Release. Sep 25, 2015 Bayer Receives FDA Approval for BETACONNECT - First and Only Electronic Autoinjector in Relapsing-Remitting Multiple Sclerosis (RRMS) Treatment. http://www.prnewswire.com/news-releases/bayer-receives-fda-approval-for-betaconnect---first-and-only-electronic-autoinjector-in-relapsing-remitting-multiple-sclerosis-rrms-treatment-300149438.html