Reading FDA briefing documents and 10-Ks for trial results and primary endpoints

The Clinical Trial & Approval Data Guide covers ClinicalTrials.gov, Drugs@FDA and EMA EPARs. This post is part 2. This time I've written up how to pull just the trial results and primary endpoints out of FDA advisory committee briefing documents and company filings.

The example is AstraZeneca's camizestrant, covered in BIO:ON Insight #16. The FDA approved it even though its advisory committee voted against, which is a good reason to read both documents side by side.

1. The case first: what happened with camizestrant

• 30 April 2026: the FDA's Oncologic Drugs Advisory Committee (ODAC) discussed the new drug application for camizestrant (NDA 220359). A combined FDA and applicant briefing document was published on the FDA website [1].
• The vote: 3 in favour, 6 against, on the benefit-risk question [2].
• 4 September 2026: the FDA granted accelerated approval for use with a CDK4/6 inhibitor in HR-positive, HER2-negative advanced breast cancer with an ESR1 mutation. The brand name is Etcamah, and confirmatory studies are required to verify clinical benefit [3].

The committee and the FDA reached different conclusions from the same data. To understand why, you need to open the briefing document itself.

2. What to look for in a briefing document

With the FDA's review and the company's material combined, a briefing document can run to hundreds of pages. Rather than reading from the start, I look for these in order.

1. The voting question and discussion questions. This is what the committee actually has to answer. Reading everything against these questions keeps you on track.
2. The primary endpoint and how it's defined. Check what was measured and from when. SERENA-6's primary endpoint was progression-free survival (PFS), and according to the FDA's approval notice it was measured from when the ESR1 mutation was first detected [3]. A definition like that changes how you read the result.
3. The FDA's key issues. This is where the FDA sets out its concerns. As reported, in the camizestrant document the FDA pointed to immature overall survival (about 30% maturity, HR 0.87, 95% CI 0.57–1.30), a trial not powered for OS, and PFS2 being hard to accept as efficacy evidence because of the protocol-triggered switch [4][5].
4. The results tables. Check medians by arm, the hazard ratio, the confidence interval and the number of events. In SERENA-6, median PFS was 16.0 versus 9.2 months, HR 0.44 (95% CI 0.31–0.60) [6].

What I've learned: the company's sections and the FDA's sections emphasise the same numbers differently. Finding one measure in both and writing them side by side taught me the most.

3. What to look for in filings: 10-K and 8-K, or 20-F and 6-K

US company filings are free to read on the SEC's EDGAR system [7].

• 10-K: the annual report. It includes the Business section and Risk Factors [8], so it's a good first stop for the big picture of a company's pipeline.
• 8-K: the current report filed when a significant event happens, generally within four business days [9].
• Foreign companies file 20-F and 6-K. A foreign private issuer listed in the US, like AstraZeneca, files its annual report on Form 20-F and interim reports on Form 6-K [10]. AstraZeneca's announcement of the ODAC vote, for example, went onto EDGAR as a 6-K [11]. So when you look up AstraZeneca on EDGAR, search for 20-F and 6-K rather than 10-K.

4. In Korea, it's DART

Korean listed companies' filings are on DART (dart.fss.or.kr), the electronic disclosure system run by the Financial Supervisory Service.

• Business report (사업보고서): the annual report, due within 90 days of the end of the financial year (Financial Investment Services and Capital Markets Act, Article 159) [12].
• Major matters report (주요사항보고서): filed when certain significant events set out in the law occur (Article 161) [13].

When a Korean biotech story mentions a licensing deal or trial result, I think it's a useful habit to check whether the same news appears as a DART filing.

5. Use AI to find the page, not to give you the number

AI is genuinely useful with documents this long. I use ChatGPT or Claude to ask where to look in a long PDF before I start reading. But I split the work like this.

• What I hand to AI: finding locations, such as "which pages have the primary endpoint definition, the voting question and the FDA's key issues?", and drafting a summary table.
• What I do myself: check every number in the table against the page it came from: medians, hazard ratios, confidence intervals and dates, one by one.

Try building the summary table like this:

• Trial name and NCT number
• Primary endpoint and when measurement starts
• Results by arm (median, HR, 95% CI) with page numbers
• Concerns the FDA raised
• Final decision (type of approval, conditions)

For checking AI answers more generally, see the checklist I use.

Exercise

1. On the FDA advisory committee calendar, open the 30 April 2026 ODAC meeting page and download the briefing document [1].
2. Find the voting question and the primary endpoint definition, and note the page numbers.
3. Compare them with the FDA's approval notice [3] and write a paragraph on what changed after the committee, or what stayed the same.
4. Find AstraZeneca's 6-K on EDGAR and compare how the company described the same events.

My own view

If an interviewer asks about a regulatory decision that caught your attention, I think it's far more convincing to say "in the briefing document the FDA's concerns were these, and it still approved under these conditions" than to repeat the news summary. It's a habit that works not only for RA, clinical and medical roles but also for BD and investment.

Sources

Official documents checked on 15 October 2026.

1. FDA — April 30, 2026: Oncologic Drugs Advisory Committee Meeting Announcement
2. OncLive — FDA ODAC Votes Against Clinical Benefit of Switching to Camizestrant in HR+ Breast Cancer After ESR1 Mutation Detection
3. FDA — FDA grants accelerated approval to camizestrant with a CDK4/6 inhibitor for ESR1-mutated HR-positive, HER2-negative locally advanced or metastatic breast cancer
4. Fierce Biotech — FDA flags concerns for AstraZeneca's camizestrant, Truqap ahead of advisory committee meeting
5. OncLive — FDA ODAC Live Updates: Committee Reviews SERENA-6 Data for Camizestrant
6. AstraZeneca (Business Wire) — Camizestrant reduced the risk of disease progression or death by 56% in SERENA-6 Phase III trial
7. Investor.gov — Using EDGAR to Research Investments
8. Investor.gov — How to Read a 10-K
9. Investor.gov — How to Read an 8-K
10. SEC — Financial Reporting Manual, Topic 6: Foreign Private Issuers
11. Stock Titan — AstraZeneca Form 6-K on the FDA ODAC vote for camizestrant
12. korea.legal — Business, half-year and quarterly reports (Capital Markets Act, Article 159)
13. korea.legal — Capital Markets Act, Article 161 (major matters reports)