Phase 3 Readout Calendar

Methodology & caveats

Why this is harder than it looks

There is no single “readout date” on any public registry. A Phase 3 trial generates three different dated events, only one of which is registered:

• Primary completion date — last patient finishes the primary endpoint analysis. This is the only event published on ClinicalTrials.gov.
• Topline announcement — the company press release / 8-K that actually moves the stock. Typically lands 3–9 months after primary completion. Not registered anywhere structured.
• Results posted to CT.gov — full data uploaded to the registry. Mandated by FDAAA within 12 months of primary completion (often hits the deadline).

Most sponsor-supplied dates are ESTIMATED and can slip silently. Plenty of "active" trials haven't been touched on CT.gov in 12+ months — the date you see may be a stale ghost.

How we label every row

We anchor on CT.gov primary completion (the only public, structured signal) and combine date type (ACTUAL vs ESTIMATED) with the time since the sponsor last updated the trial record:

• Read out — results have been posted to ClinicalTrials.gov (definitive).
• Completed · awaiting — primary completion is ACTUAL but no results yet (topline often already announced; sponsor has 12 months under FDAAA to post).
• Estimated · fresh / aging / stale — sponsor estimate, with last-update freshness in 3 buckets (≤6 mo / 6–12 mo / >12 mo).

What we explicitly don't claim

We do not predict topline announcement dates and we do not score per-trial slip risk. Both would require SEC EDGAR full-text NCT linking and historical version snapshots — separate enrichments we've scoped but not built. Other free retail calendars conflate ACTUAL/ESTIMATED dates and don't flag staleness; we label them so you don't have to guess which dates are credible.

Coverage

Source: ClinicalTrials.gov v2 API. We list industry-sponsored Phase 3 trials with primary completion in the last 6 months or next 12+ months. Excluded: TERMINATED, WITHDRAWN, SUSPENDED. Phase 2 readouts are out of scope today (5x volume, separate sprint).