Background
Phase III, open-label, 2×2 factorial RCT (GHSG HD13). 1,710 randomized patients (1,502 in final analysis) with early-stage favorable classical Hodgkin lymphoma (cHL, GHSG criteria). Designed to test whether bleomycin, dacarbazine, or both could be safely omitted from the ABVD backbone while maintaining efficacy. The four arms were ABVD (full), AVD (no bleomycin), ABV (no dacarbazine), and AV (neither).
Interventions and follow up
Arm A (reference): ABVD — doxorubicin 25mg/m² + bleomycin 10mg/m² + vinblastine 6mg/m² + dacarbazine 375mg/m² IV days 1 and 15, q28d × 2 cycles, followed by 30 Gy IFRT
Other arms: AVD (no bleomycin), ABV (no dacarbazine), AV (neither) × 2 + 30 Gy IFRT
Primary endpoint: Freedom from treatment failure (FFTF)
Median follow up: 90.8 months
Other arms: AVD (no bleomycin), ABV (no dacarbazine), AV (neither) × 2 + 30 Gy IFRT
Primary endpoint: Freedom from treatment failure (FFTF)
Median follow up: 90.8 months
Results
5-year FFTF (ABVD): 93.1% (reference)
FFTF (AVD, no bleomycin): 81.4% — inferior (difference 11.5%, 95% CI 6.7–16.3)
FFTF (ABV, no dacarbazine): 89.2% — inferior
FFTF (AV): 77.1% — arm closed early (IDMC), significantly inferior
5-year OS: 97–98% across arms — no significant differences
FFTF (AVD, no bleomycin): 81.4% — inferior (difference 11.5%, 95% CI 6.7–16.3)
FFTF (ABV, no dacarbazine): 89.2% — inferior
FFTF (AV): 77.1% — arm closed early (IDMC), significantly inferior
5-year OS: 97–98% across arms — no significant differences
Adverse events
Pulmonary: Bleomycin-containing arms grade ≥3 pulmonary toxicity ~2–3%
Gastrointestinal/hematologic: Higher grade ≥3 nausea/emesis (~15%) in dacarbazine-containing arms; overall toxicity modest for 2-cycle regimens with no excess hematologic toxicity across arms
Gastrointestinal/hematologic: Higher grade ≥3 nausea/emesis (~15%) in dacarbazine-containing arms; overall toxicity modest for 2-cycle regimens with no excess hematologic toxicity across arms
Conclusions
Neither bleomycin nor dacarbazine can be safely omitted from ABVD for early-stage favorable cHL — all modified regimens showed inferior FFTF. 2×ABVD + 30 Gy IFRT remains the established standard, although HD10 subsequently showed 2×ABVD + 20 Gy is equally effective with less radiation toxicity.
Key Limitations
The 30 Gy IFRT comparator predates the HD10 demonstration that 20 Gy suffices. No chemotherapy-only arm was included, and all arms used IFRT, so radiation-free strategies cannot be evaluated. Contemporary practice uses INRT/ISRT rather than IFRT, reducing radiation volumes. The AV arm was closed early on IDMC recommendation, limiting its interpretation.
Clinical Context
HD13 established that both bleomycin and dacarbazine are essential components of ABVD for early-stage favorable HL — even single-agent omission significantly compromises disease control. Combined with HD10, the evidence supports 2×ABVD + 20 Gy INRT as standard of care for GHSG-defined early-stage favorable cHL per ESMO and ASCO guidance. PET-adapted strategies (RAPID, H10) subsequently explored omitting RT in PET-negative patients.