Dosing and uses of Rescriptor (delavirdine)
Adult dosage forms and strengths
tablet
- 100mg
- 200mg
HIV-1 Infection
400 mg PO TID with other antiretrovirals
Solution administration
- Add 100 mg-tablets (4 tablets totaling 400 mg) in at least 3 oz water; allow to stand for few minutes
- Do NOT use 200 mg tablets (not well-dispersed in water)
- Stir slurry until mixed uniformly; consume promptly
- Rinse glass with water and swallow entire contents of rinse
Other Information
Used in combination with at least 2 other antiretroviral agents
Pediatric dosage forms and strengths
<16 years old: Safety and efficacy not established
Rescriptor (delavirdine) adverse (side) effects
>10%
Rash (32-35%)
1-10%
Headache
Fatigue
Pruritus
Diarrhea
Vomiting
Increased ALT/ASt
Warnings
Black box warnings
Indicated for use only in combination with appropriate antiretroviral drugs
Resistant virus emerges rapidly when delavirdine is administered as monotherapy
Contraindications
Hypersensitivity
Coadministration with drugs highly dependent on CYP3A4 for clearance and those for which elevated plasma levels are associated with serious or life-threatening events (eg, dihydroergotamine, ergonovine, ergotamine, methylergonovine, cisapride, pimozide, alprazolam, midazolam, triazolam)
Coadministration with drugs (eg, CYP inducers) where significant decreases in delavirdine plasma concentrations may occur, which may result in loss of virologic response and possible resistance and cross-resistance to other NNRTIs
Cautions
Use only in combination with other agents - delavirdine alone results in rapid resistance
Patients with achlorhydria should take with acidic juice
Avoid antacids 1 hr prior to and after administration
Discontinue if severe rash or rash with associated mucocutaneous lesions; erythema multiforme and Stevens-Johnson Syndrome
Avoid St John's wort: may result in loss of virologic response/resistance
Hepatic impairment
Risk of cross resistance to other NNRTI
Risk of immune reconstitution syndrome if used in combination with other antiretroviral drugs
Pregnancy and lactation
Pregnancy category: C
Lactation: Not known whether distributed into milk. Because of both the potential for HIV transmission and the potential for serious adverse reactions in nursing infants, mothers should be instructed not to breastfeed.
Health professionals should contact the antiretroviral pregnancy registry to monitor outcomes of pregnant women exposed to delavirdine or other antiretroviral medications by calling 1-800-258-4263 or going to www.APRegistry.com.
Pregnancy categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.
C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.
D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.
X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.
NA: Information not available.
Pharmacology of Rescriptor (delavirdine)
Absorption: rapid
Distribution: low concentration in saliva & semen; CSF 0.4% concurrent plasma concentration
Protein Bound: ~98%, primarily albumin
Bioavailability: 85%; ~20% incr w/ slurry
Half-life: 5.8 hr (mean)
Peak Plasma Time: 1 hr
Metabolism: hepatic via CYP3A4 & 2D6
Excretion: urine (51%, <5% as unchanged drug); feces (44%)
Mechanism of action
Non-Nucleoside Reverse Transcriptase Inhibitor (NNRTI) of HIV-1
Directly binds to reverse transcriptase and inhibits RNA- & DNA-dependent DNA polymerase
