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The open RA library

Everything we
wish we’d known
about FDA.

Visual explainers, interactive tools, a glossary of regulatory terms you can finally Google, a newsroom that tracks what FDA actually does — and templates we’d hand to a friend.

By the numbers
153
Articles & explainers
8
Interactive tools
630+
Glossary terms
Daily
Newsroom updates

Featured this week

Interactive Explainer

The 510(k) flow, end-to-end — every gate, decision, and FDA touchpoint.

From concept to clearance: 14 stops on the most-traveled FDA pathway, with every form and fee in context. Click any stop to dive deep.

14 min · VisualUpdated this week

Interactive tools

Explainers & long-reads

Showing 3 of 153 · View all 153
Market Entry & Strategy
May 5, 2026 · ~8 MIN

Does My Mobile Health App Need FDA Approval or Clearance? When Your iOS/Android App Is a Medical Device Explained

Discover if your Mobile Health App needs FDA approval. Learn when a Mobile Health App is considered a medical device and the steps to compliance.

Software, AI & SaMD
SaMD
Apr 30, 2026 · ~8 MIN

Software as a Medical Device (SaMD) Explained: What It Is, FDA Requirements, and How to Get Cleared

Explore the world of software as a medical device, understand FDA requirements, and learn how to get your software as a medical device cleared efficiently.

Post-Market
AI
Apr 27, 2026 · ~8 MIN

FDA’s Latest Warning Letter Mentions AI. Here’s What Actually Matters.

FDA cited AI in a warning letter. Here is what actually happened, why the company failed, and what it means for every team using AI in regulated work.

Newsroom · FDA tracker

Every CDRH guidance, warning letter, and recall that matters — distilled and dated.

OCT 24, 2025

FDA finalizes guidance on Predetermined Change Control Plans for AI/ML

The long-awaited PCCP final guidance lands. We summarize what's different from the draft, who it affects, and three things to add to your next AI submission.

Guidance
OCT 18, 2025

Warning letter cites inadequate cybersecurity in connected glucose monitor

A FY26 enforcement action that signals where 524B compliance bites. The 5 specific gaps named in the letter.

Enforcement
OCT 11, 2025

FY26 user fee schedule released — small-business 510(k) drops 3.4%

The first decrease in 8 years. A surprise win for early-stage filers. Updated fee table with eligibility rules.

Fees
OCT 04, 2025

Class I recall: cardiac monitoring software, 14 reported incidents

What the public 21 CFR 806 filing tells us about software change control failures.

Recall
SEP 27, 2025

CDRH proposes new product code framework for digital therapeutics

A draft restructuring of how DTx are coded. Public comment closes Dec 15.

Pathway

Glossary · the dictionary RA actually needs

Every term plain-English defined, cited to the regulation, with linked terms for the rabbit-hole.

510(k)/ˌfaɪv-ˈten-keɪ/

Premarket notification demonstrating substantial equivalence to a legally marketed predicate device. The most common FDA pathway for Class II devices.

21 CFR 807 Subpart E
De Novo/dɛ ˈnoʊvoʊ/

Pathway for novel low-to-moderate-risk devices without a predicate. Creates a new classification regulation if granted.

21 CFR 860.200
Predicate

A legally marketed device used to demonstrate substantial equivalence in a 510(k). Cannot be one withdrawn for safety reasons.

FD&C Act §513(i)(1)(A)
Substantial Equivalence

The standard for 510(k) clearance. Requires same intended use plus same OR different technology that doesn't raise new safety questions.

FD&C Act §513(i)
eSTAR

FDA's electronic submission template for 510(k) and De Novo. Mandatory since Oct 2023. Replaces eCopy.

CDRH eSTAR Guidance
Refuse to Accept (RTA)

FDA's pre-substantive review checklist. A submission that fails RTA gets bounced before review starts. ~30% fail on first try.

CDRH RTA Checklist 2024
Q-Submission

Pre-submission program to get FDA feedback before filing. Free. Adds ~75 days but often saves 6+ months downstream.

Q-Sub Guidance, 2023
PCCP/pee-see-see-pee/

Predetermined Change Control Plan. Lets AI/ML devices specify allowed future changes upfront, avoiding repeat 510(k)s.

PCCP Final Guidance, Oct 2025
SaMD

Software as a Medical Device. Software intended to perform a medical function without being part of a hardware device.

IMDRF SaMD WG Documents

Templates & downloadable resources

Free templates we’ve cleaned up from real submissions. Use them. Edit them. Tell us what’s missing.

510(k) Cover Letter Template

Premarket · Section 1
WordDownload →

Substantial Equivalence Comparison Table

Premarket · Section 5
ExcelDownload →

ISO 14971 Risk Management Plan

Risk · Plan · §4
WordDownload →

FMEA Worksheet (Design + Process)

Risk · Analysis
ExcelDownload →

Indications for Use Statement (Form 3881)

Premarket · Section 4
WordDownload →

Q-Submission Cover & Question List

Pre-Sub · Q-Sub
WordDownload →

Design History File Trace Matrix

DHF · Traceability
ExcelDownload →

FDA RTA Pre-flight Checklist

Premarket · Acceptance
PDFDownload →