A Japanese Language Model and Three New Evaluation Benchmarks for Pharmaceutical NLP
Shinnosuke Ono, Issey Sukeda, Takuro Fujii, Kosei Buma, Shunsuke Sasaki
Abstract
We present **JPharmatron**, a Japanese domain-specific large language model (LLM) for the pharmaceutical field, developed through continual pre-training on two billion Japanese pharmaceutical tokens and eight billion English biomedical tokens. For rigorous evaluation, we introduce **JPharmaBench**, a benchmark suite consisting of three new benchmarks: YakugakuQA, based on national pharmacist licensing exams; NayoseQA, which tests cross-lingual synonym and terminology normalization; and SogoCheck, a novel task involving cross-document consistency checking.We evaluate our model against open-source medical LLMs and commercial models, including GPT-4o. Experimental results show that **JPharmatron** outperforms existing open models and achieves competitive performance with commercial ones.Interestingly, even GPT-4o performs poorly on SogoCheck, suggesting that cross-sentence consistency reasoning remains an open challenge.**JPharmatron** enables secure and local model deployment for pharmaceutical tasks, where privacy and legal constraints limit the use of closed models. Besides, **JPharmaBench** offers a reproducible framework for evaluating Japanese pharmaceutical natural language processing. Together, they demonstrate the feasibility of practical and cost-efficient language models for Japanese healthcare and pharmaceutical sectors.Our model, codes, and datasets are available on HuggingFace: https://huggingface.co/collections/EQUES/jpharmatron and https://huggingface.co/collections/EQUES/jpharmabench.- Anthology ID:
- 2025.ijcnlp-long.72
- Volume:
- Proceedings of the 14th International Joint Conference on Natural Language Processing and the 4th Conference of the Asia-Pacific Chapter of the Association for Computational Linguistics
- Month:
- December
- Year:
- 2025
- Address:
- Mumbai, India
- Editors:
- Kentaro Inui, Sakriani Sakti, Haofen Wang, Derek F. Wong, Pushpak Bhattacharyya, Biplab Banerjee, Asif Ekbal, Tanmoy Chakraborty, Dhirendra Pratap Singh
- Venues:
- IJCNLP | AACL
- SIG:
- Publisher:
- The Asian Federation of Natural Language Processing and The Association for Computational Linguistics
- Note:
- Pages:
- 1316–1332
- Language:
- URL:
- https://preview.aclanthology.org/ingest-ijcnlp-aacl/2025.ijcnlp-long.72/
- DOI:
- Cite (ACL):
- Shinnosuke Ono, Issey Sukeda, Takuro Fujii, Kosei Buma, and Shunsuke Sasaki. 2025. A Japanese Language Model and Three New Evaluation Benchmarks for Pharmaceutical NLP. In Proceedings of the 14th International Joint Conference on Natural Language Processing and the 4th Conference of the Asia-Pacific Chapter of the Association for Computational Linguistics, pages 1316–1332, Mumbai, India. The Asian Federation of Natural Language Processing and The Association for Computational Linguistics.
- Cite (Informal):
- A Japanese Language Model and Three New Evaluation Benchmarks for Pharmaceutical NLP (Ono et al., IJCNLP-AACL 2025)
- PDF:
- https://preview.aclanthology.org/ingest-ijcnlp-aacl/2025.ijcnlp-long.72.pdf