Protagonist Therapeutics

Protagonist Therapeutics, Inc. is a clinical-stage biopharmaceutical company headquartered in Newark, California and founded in 2006. It discovers and develops peptide-based new chemical entities using a proprietary peptide discovery and engineering platform, targeting rare and prevalent diseases with significant unmet medical need. Lead programs include rusfertide, a hepcidin mimetic in Phase 3 for polycythemia vera, and icotrokinra (PN-235), an oral IL-23 receptor antagonist partnered with Johnson & Johnson. The company is publicly traded (Nasdaq: PTGX) following its 2016 IPO. It was surfaced as a portfolio company of Canaan Partners and added to the API Evangelist network; enrichment found no public developer API, OpenAPI, SDK, or agent surface.

Protagonist Therapeutics is profiled on the APIs.io network. Tagged areas include Company, Biopharmaceutical, Biotechnology, Peptide Therapeutics, and Pharmaceuticals.

Protagonist Therapeutics’ developer surface includes engineering blog and 6 more developer resources.

🌐 Visit website 📡 Source on GitHub

14.3/100 minimal ▬ flat Agent 0/100 human only Full breakdown ↓
scored 2026-07-27 · rubric v0.5

0 APIs

CompanyBiopharmaceuticalBiotechnologyPeptide TherapeuticsPharmaceuticalsDrug DiscoveryHealthcareLife Sciences

Kin Score

Kin Score How this is scored →
scored 2026-07-27 · rubric v0.5

Composite quality — 14.3/100 · minimal

Contract Quality 0.0 / 25

Developer Ergonomics 0.4 / 20

Commercial Clarity 4.2 / 20

Operational Transparency 0.0 / 13

Governance 0.0 / 12

Discoverability 6.8 / 10

Agent readiness — 0/100 · human only

Machine-Readable Contract 0 / 18

Agentic Access Contract 0 / 15

MCP Server 0 / 12

Machine-Readable Auth 0 / 10

Idempotency 0 / 9

Stable Error Semantics 0 / 8

Request/Response Examples 0 / 7

Rate-Limit Signaling 0 / 7

Typed Event Surface 0 / 6

Agent Skills 0 / 5

Well-Known Catalog 0 / 4

Consent & Bot Identity 0 / 3

Improve this rating by publishing the missing artifacts — every area above can be raised, and the full rubric is at apis.io/rating/. This rating is computed from github.com/api-evangelist/protagonist-therapeutics: open an issue to ask a question, or submit a pull request to add artifacts. Want it done for you? Prioritized profiling — $2,500 →

Access & Security 1

Authentication, authorization, and security posture

DomainSecurity

DomainSecurity

Operate 1

Status, limits, changes, and where to get help

Contact

Contact

Commercial 2

Pricing, plans, and the legal terms of use

PrivacyPolicy

PrivacyPolicy

TermsOfService

TermsOfService

Company 3

The organization behind the API

Website

Website

Blog

Blog

LinkedIn

Source (apis.yml)

aid: protagonist-therapeutics
accessModel:
  pricing: unknown
  onboarding: unknown
  trial: false
  try_now: false
  public: false
  label: Unknown
  confidence: low
  source: []
  generated: '2026-07-22'
  method: derived
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/protagonist-therapeutics.png
name: Protagonist Therapeutics
description: 'Protagonist Therapeutics, Inc. is a clinical-stage biopharmaceutical company headquartered in Newark, California
  and founded in 2006. It discovers and develops peptide-based new chemical entities using a proprietary peptide discovery
  and engineering platform, targeting rare and prevalent diseases with significant unmet medical need. Lead programs include
  rusfertide, a hepcidin mimetic in Phase 3 for polycythemia vera, and icotrokinra (PN-235), an oral IL-23 receptor antagonist
  partnered with Johnson & Johnson. The company is publicly traded (Nasdaq: PTGX) following its 2016 IPO. It was surfaced
  as a portfolio company of Canaan Partners and added to the API Evangelist network; enrichment found no public developer
  API, OpenAPI, SDK, or agent surface.'
url: https://raw.githubusercontent.com/api-evangelist/protagonist-therapeutics/refs/heads/main/apis.yml
x-type: company
x-source: vc-portfolio
x-backed-by:
- canaan-partners
x-tier: stub
x-tier-reason: portfolio-lead
specificationVersion: '0.20'
created: '2026-07-17'
modified: '2026-07-20'
tags:
- Company
- Biopharmaceutical
- Biotechnology
- Peptide Therapeutics
- Pharmaceuticals
- Drug Discovery
- Healthcare
- Life Sciences
apis: []
common:
- type: DomainSecurity
  url: security/protagonist-therapeutics-domain-security.yml
- type: Website
  url: https://www.protagonist-inc.com/
- type: Blog
  url: https://www.protagonist-inc.com/news
- type: PrivacyPolicy
  url: https://www.protagonist-inc.com/privacy-policy
- type: TermsOfService
  url: https://www.protagonist-inc.com/terms-of-use
- type: Contact
  url: https://www.protagonist-inc.com/contact
- type: LinkedIn
  url: https://www.linkedin.com/company/protagonist-therapeutics
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
- FN: APIs.json
  email: info@apis.io
x-enrichment:
  date: '2026-07-20'
  status: minimal
  artifacts_added: 1
  pass: local-v1