A synergistic combination reduces the necessary dose of Drug A by 4-fold while maintaining clinical efficacy. Which clinical consideration should most strongly influence whether to adopt this combination as standard therapy?

• A. Balance the decreased toxicity from lower Drug A dose against any increased toxicity or logistical concerns introduced by the partner drug (e.g., its adverse effects, monitoring requirements, or cost), and weigh evidence from randomized trials rather than in vitro synergy alone.
• B. Immediately change guidelines to mandate the combination because dose reductions in vitro translate directly into reduced adverse events in every patient regardless of comorbidities, pharmacokinetics, or microbial ecology.
• C. Avoid combinations that lower doses since lower dosing always increases the risk of emergent resistance and treatment failure, even if synergy is demonstrated in multiple clinical trials.
• D. Adopt the combination without adjusting therapeutic drug monitoring practices, because reduction in dose completely eliminates the need to monitor drug concentrations or organ function.

Answer: (A)