Plain Language Summaries PLS improve health literacy and enable informed healthcare decisions but writing them requires domain expertise and is time-consuming. Automated methods often prioritize efficiency over comprehension and medical documents unique simplification requirements challenge generic solutions. We present a multi-agent system for generating PLS using Cochrane PLS as proof of concept. The system uses specialized agents for information extraction writing diagnosis and evaluation integrating a medical glossary and statistical analyzer to guide revisions. We evaluated three architectural configurations on 100 Cochrane abstracts using six LLMs both proprietary and open-source. Results reveal model-dependent trade-offs between factuality and readability with the multi-agent approach showing improvements for smaller models and providing operational advantages in control and interpretability.