OnCo

VAC (vincristine, dactinomycin, cyclophosphamide)

Checked 2026-09-09

Backbone chemotherapy for childhood rhabdomyosarcoma in the Intergroup and Children's Oncology Group trials, with surgery and radiotherapy

Also called VAC.

One cycle

every 21 days × 14 · about 42 weeks in total
178141521Vincristine: 1.5 mg/m² (maximum 2 mg), IntravenousVincristineDactinomycin: 0.045 mg/kg (maximum 2.5 mg), IntravenousDactinomycinCyclophosphamide: 2.2 g/m² with mesna, IntravenousCyclophosphamide
21-day cycle × 14 (about 42 weeks) in IRS-IV (about 42 weeks)Intravenous

Components

DrugDoseRouteDays
Vincristine
Vinca alkaloid (microtubule inhibitor)
1.5 mg/m² (maximum 2 mg)IVD1, 8, 15
Dactinomycin
Actinomycin antibiotic (transcription inhibitor)
0.045 mg/kg (maximum 2.5 mg)IVD1
Cyclophosphamide
Alkylating agent (oxazaphosphorine prodrug)
2.2 g/m² with mesnaIVD1
Cycles
14 (about 42 weeks) in IRS-IV
21-day cycle
Emetogenicity
High (>90%)
G-CSF
Recommended

Notes

  • Later COG trials reduced the cyclophosphamide dose (1.2 g/m²) and added irinotecan (VAC/VI) for intermediate-risk disease.
  • Radiotherapy is given to the primary site for all but completely resected embryonal tumours.

Used in

Source

Crist (IRS-IV), JCO 2001: VAC versus VAI versus VIE in non-metastatic rhabdomyosarcoma

Reference doses for a typical adult from the cited protocol or label. Doses are adjusted for renal and hepatic function, age, performance status and prior toxicity, and institutional protocols vary. Verify against the current label and your local protocol before treating. Not medical advice.