Are Two LLMs Better Than One? A Student-Teacher Dual-Head LLMs Architecture for Pharmaceutical Content Optimization
Organizations: Roche · Accenture · Involead
Abstract
Large Language Models (LLMs) are increasingly used for content creation in regulated domains such as pharmaceuticals, where content must be medical accurate and legally compliant. Traditional manual quality control (QC) is slow, error-prone, and create publication bottlenecks. To address this, we introduce a modular, LLM/VLMs-driven QC architecture, LRBTC (Language, Regulatory, Brand, Technical, Content Structure), implemented through a Student Teacher HITL architecture and Waterfall rule filtering logic for scalable, verifiable content validation. This architecture is designed to provide verifiable, traceable, and scalable content optimization. Our methods achieve 83.0% F1 and 97.5% recall on AIReg Bench, reducing missed violations five fold compared with Gemini 2.5 Pro. On CSpelling, it improves mean accuracy by +26.7 %. Our error analysis further reveals that while current models are strong at detecting misspellings (92.5% recall), they fail to identify complex grammatical (25.0% recall) and punctuation (41.7% recall) errors, highlighting a key area for future work. This work provides a practical, plug-and-play solution for reliable, transparent quality control of content in high-stakes, compliance-critical industries. We also provide demo access.
Figures & tables
| Sample Set | Gemini 2.5 Pro | Gemini 2.5 Pro | Our | Our | |
| Size | Mean (%) | SD (%) | Mean (%) | SD (%) | (%) |
| 10 | 17.6 | 26.6 | 34.4 | 25.9 | +16.8 |
| 12 | 13.5 | 18.3 | 43.7 | 27.0 | +30.1 |
| 12 | 29.5 | 31.3 | 57.9 | 32.2 | +28.4 |
| 12 | 21.2 | 23.5 | 48.0 | 28.2 | +26.8 |
| 10 | 24.2 | 31.0 | 41.1 | 34.8 | +16.9 |
| Error | Total Occurrences | Detection |
| Class | (GT) | (Recall %) |
| Misspelling | 200 | 92.5 |
| ToSplit / ToMerge | 100 | 65.0 |
| Punctuation | 60 | 41.7 |
| Grammar | 100 | 25.0 |
| Informal / Word not exists | 40 | 12.5 |
Appendix figures & tables11 assets
Supplementary material from the paper’s appendix.
Appendix
| Provider/Model | Sample Tokens | Cost | / 1K tok |
| Gemini 2.5 Pro | 2.4K | 3.39¢ | 1.41¢ |
| Gemini 2.5 Pro | 5.0K | 7.46¢ | 1.49¢ |
| Gemini 2.5 Flash | 1.9K | 0.64¢ | 0.34¢ |
| Gemini 2.5 Flash | 1.8K | 0.38¢ | 0.21¢ |
| Anthropic (Claude) | 11.0K | 3.51¢ | 0.32¢ |
| Anthropic (Claude) | 11.9K | 3.93¢ | 0.33¢ |
| Metric | Value |
| Total tokens Per week | 12.3M |
| Total requests | 2,000 |
| Latency (P50) | 2010 ms |
| Cost / request | $0.02045 |
| Tokens / request | 6,150 |
| Model | Mean Accuracy (%) | SD (%) |
| Gemini Pro | 15.1 | 21.7 |
| (Gemini 2.5 Pro Teacher + Gemini 2.5 Flash Student) | 40.1 | 26.4 |
| (Gemini 2.5 Pro Teacher + Claude 3.5 Sonnet Student) | 48.1 | 27.3 |
| Metric | Student-Teacher Methods (%) | Student-Teacher Methods |
| (Gemini 2.5 Pro as Teacher | (Gemini 2.5 Pro Teacher + | |
| + Claude 3.5 Sonnet as Student) | + Gemini 2.5 Flash Student) | |
| Accuracy ( ) | 42.45 | 65.67 |
| Recall ( ) | 63.89 | 95.00 |
| Precision ( ) | 49.36 | 64.41 |
| F1-Score | 55.68 | 76.86 |
| Specialty | Audio | Video | Specialty | Audio | Video |
| Oncology | 208 | 8934 | Ophthalmology | 159 | 2862 |
| Sample setiovascular | 1 | 14 | Respiratory Disease | 16 | 467 |
| Dermatology | 0 | 30 | Nephrology | 1 | 380 |
| Hematology | 67 | 3606 | Not Applicable | 59 | 2853 |
| Immunology | 144 | 510 | Movement Disorder | 9 | 289 |
| Infectious Disease | 1 | 239 | Inflammatory Disease | 20 | 222 |
| System Prompt | Content |
| System Role | You are an expert in corporate communications and compliance . Review the user’s text against the following Foundation QC (Quality Control) rules. Using Default Global Copy Style Guide Book. Focus on UK English spelling and grammar unless otherwise specified. |
| Spelling Rules – What to Do | • 1.1 Use UK English for all corporate communications. • 1.2 For non-commercial or internal use, generally follow UK spelling, unless content is purely for a US audience or the brief requires US spelling. • 1.3 Use “analogue” when meaning “something similar to something else” or referring to chemical compounds. • 1.4 Check the BNF (medicines.org.uk/emc) for correct spelling of UK proprietary and generic drug names. …… |
| Spelling Rules – What to Prohibit | • 2.1 Avoid US spellings in UK English such as acknowledgment, etiology, aging, anemia, anesthetic, analog, behavior, cesarean, center, coloration, corticotropin, dialog (except for UI), diarrhea, dyspnea, enroll, favor, … practice (verb), program (unless IT), signaling, sulfur, tumor. • 2.2 Do not add spaces around ampersands. • 2.3 Do not use -t where -ed is preferred (learnt, spelt, burnt). • 2.4 Do not use -ize in UK English except defined exceptions. …… |
| Other Comments | Officially uses UK English for all corporate communications. Exceptions apply for US audiences or specific briefs. The rulebook contains UK vs US spellings, ampersand usage, drug naming standards, past tense guidance, and rules for -ise/-ize. |
| Analysis Requirements (Chain-of-Thought) | 1. Carefully examine the plans against each relevant rule in the rule books 2. Identify any areas where the plans may not comply with the rules 3. Cite specific rules when discussing compliance issues 4. Consider both explicit requirements and implicit principles in the rule books |
| Output Format | Respond with a JSON object. The object should have a single key "issues" which is an array of objects. Each violation must include: 1. "issue" rule ID (MUST HAVE) for the rule that was violated 2. "context" The exact text snippet from the user’s content where the violation occurred 3. "recommendation" A clear suggestion on how to fix the violation. If no issues are found, return "issues": [] . |
| System Prompt | Content |
| System Role | You are a compliance and regulation expert. I will provide you with content from a document (text or an image). Your task is to carefully analyze the document and extract all the rules into a JSON file format. |
| Task Overview | The JSON object should include the document’s title, a summary of its content, and any other general comments. It must also contain a sections array, where each section details a specific set of rules, including what to do, what to prohibit, and any other relevant comments. |
| Critical Instruction | When extracting rules for what_to_do and what_to_prohibit , you MUST use the exact wording, phrasing, and sentences from the original document. Do not rephrase, summarize, or generate new text for the rules. Copy them verbatim from the source. |
| Required JSON Structure | { "documentInfo": { "title": "Document Title Here", "content_about": "A brief description of this document.", "other_comments": "Any other general comments about the document." }, "sections": [ { "title": "Title of the Rule Section", "content_about": "Description of this rule section.", "what_to_do": ["Rule 1 of what to do.", "Rule 2..."], "what_to_prohibit": ["Rule 1 of what to avoid.", "Rule 2..."], "other_comments": "Optional comments for this specific section." } ] } |
| Final Instruction | Now, analyze the following content and provide the structured JSON output. |
| Prompt | Content |
| Task Description | Verification Task using a teacher model to perform authoritative final review of previously flagged issues. |
| Original Text | ${userText} |
| Original Rules | ${currentSystemInstruction} |
| Issues to Re-evaluate | The following issues were identified by different models and require a final, authoritative check. {issuesToVerify.map(i => ‘- Rule: {i.issue} { Context: "{i.context}"‘).join(’\n’)} |
| Teacher Model Instructions | 1. Critically re-evaluate each issue against the original text and rules. 2. If multiple issues point to the same underlying error (e.g., a single typo violating two different spelling rules), consolidate them into a single issue in your response. 3. For each final issue, determine if it is a valid violation. |
| Output Format Requirements | Respond with a JSON object. The object must have a single key "issues" which is an array of objects. Each object represents one of the re-evaluated issues and must have the following FOUR keys: 1. "issue" : The most appropriate rule ID for the violation. 2. "context" : The exact snippet from the user text. 3. "recommendation" : Your final verdict and justification. If it is NOT a valid violation, explain why it was likely flagged incorrectly. 4. "isValid" : A boolean value. Set to ’true’ if the issue is a valid violation, and ’false’ otherwise. |