Step-Up and Bombard Techniques in Rheumatoid Arthritis Treatment
The step-up and bombard techniques are two contrasting treatment approaches for rheumatoid arthritis, with the step-up approach starting with methotrexate monotherapy and adding medications sequentially if targets aren't met, while the bombard approach initiates combination therapy immediately with multiple DMARDs or biologics to rapidly suppress disease activity.
Step-Up Approach
The step-up approach is the most commonly recommended strategy for treating rheumatoid arthritis, particularly in patients without poor prognostic factors:
- Initial Treatment: Start with methotrexate (MTX) monotherapy at 15 mg/week with folic acid supplementation (1 mg/day) 1, 2
- Dose Optimization: Escalate MTX to 20-25 mg/week within 4-6 weeks as tolerated 1, 2
- Critical Assessment Point: Evaluate response at 3 months - this is the most useful time to assess probability of attaining remission at 1 year 1, 2
- Sequential Addition: If target not reached by 3-6 months, add additional medications in a step-wise fashion:
Evidence Supporting Step-Up Approach
The TEAR (Treatment of Early Aggressive Rheumatoid Arthritis) trial showed no advantages of initial combination therapy incorporating etanercept over initial MTX monotherapy with step-up to combination therapy at 6 months in patients with inadequate response 1. This supports the step-up approach as both cost-effective and clinically sound.
Bombard Approach
The bombard approach (also called initial combination therapy) involves:
- Immediate Combination: Starting with multiple DMARDs or a DMARD plus biologic agent from the beginning of treatment
- Target Population: Reserved for patients with high disease activity and poor prognostic factors (high RF/ACPA, early joint damage) 1, 2
- Common Combinations:
- MTX + TNF inhibitor (adalimumab, etanercept)
- MTX + other biologic agents (abatacept)
- MTX + other conventional DMARDs (sulfasalazine, hydroxychloroquine)
Evidence for Bombard Approach
Some studies suggest that combination of MTX with a TNF inhibitor or CTLA-4:Ig (abatacept) has greater efficacy than MTX monotherapy for both clinical and radiographic outcomes in patients with poor prognostic factors 1. However, this approach has limitations including higher costs and potentially unnecessary exposure to more aggressive therapy for patients who might respond to simpler regimens.
When to Choose Each Approach
- Step-Up Approach: Preferred for most patients, especially those without poor prognostic factors 1, 2
- Bombard Approach: Consider for patients with:
Common Pitfalls to Avoid
- Inadequate MTX dosing: Optimal dose is 20-25 mg/week; lower doses may lead to treatment failure 2
- Omitting folic acid supplementation: Reduces GI side effects, hepatic dysfunction, and improves MTX continuation rates 2, 3
- Delayed treatment adjustment: If no improvement after 3 months or target not reached by 6 months, therapy must be adjusted 2
- Prolonged glucocorticoid use: Should be tapered within 6 months to minimize adverse effects 2
Monitoring and Treatment Targets
- Target: Remission (SDAI ≤3.3, CDAI ≤2.8) or low disease activity (SDAI ≤11, CDAI ≤10) 1, 2
- Monitoring: Every 1-3 months in active disease 2
- Response Assessment: More than 75% of patients with low disease activity or remission at 3 months will be in remission at 1 year 1, 2
The evidence supports that the step-up approach is appropriate for most patients, while the bombard approach should be reserved for those with high disease activity and poor prognostic factors where rapid disease control is essential to prevent irreversible joint damage.