Benchmarking GPT-5 for biomedical natural language processing (2509.04462v1)

Abstract: The rapid expansion of biomedical literature has heightened the need for scalable NLP solutions. While GPT-4 substantially narrowed the gap with task-specific systems, especially in question answering, its performance across other domains remained uneven. We updated a standardized BioNLP benchmark to evaluate GPT-5 and GPT-4o under zero-, one-, and five-shot prompting across 12 datasets spanning six task families: named entity recognition, relation extraction, multi-label document classification, question answering, text summarization, and text simplification. Using fixed prompt templates, identical decoding parameters, and batch inference, we report primary metrics per dataset and include prior results for GPT-4, GPT-3.5, and LLaMA-2-13B for comparison. GPT-5 achieved the strongest overall benchmark performance, with macro-average scores rising to 0.557 under five-shot prompting versus 0.506 for GPT-4 and 0.508 for GPT-4o. On MedQA, GPT-5 reached 94.1% accuracy, exceeding the previous supervised state of the art by over fifty points, and attained parity with supervised systems on PubMedQA (0.734). In extraction tasks, GPT-5 delivered major gains in chemical NER (0.886 F1) and ChemProt relation extraction (0.616 F1), outperforming GPT-4 and GPT-4o, though summarization and disease NER still lagged behind domain-specific baselines. These results establish GPT-5 as a general-purpose model now offering deployment-ready performance for reasoning-oriented biomedical QA, while precision-critical extraction and evidence-dense summarization continue to favor fine-tuned or hybrid approaches. The benchmark delineates where simple prompting suffices and where retrieval-augmented or planning-based scaffolds are likely required, providing actionable guidance for BioNLP system design as frontier models advance.