aid: upstream-bio
name: Upstream Bio
description: >-
  Upstream Bio is a clinical-stage biotechnology company headquartered at 460 Totten Pond Road in
  Waltham, Massachusetts, founded in 2021 and listed on Nasdaq as UPB since its October 2024 IPO. The
  company develops treatments for inflammatory disease with an initial focus on severe respiratory
  disorders, and its strategy is built around a single lead asset: verekitug (UPB-101), described by
  the company as the only known antagonist in clinical development that targets the receptor for
  thymic stromal lymphopoietin (TSLP). Verekitug has been advanced into Phase 2 studies in severe
  asthma, chronic rhinosinusitis with nasal polyps (CRSwNP) and chronic obstructive pulmonary disease
  (COPD), with a Phase 3 development strategy announced in 2026. Upstream Bio is a therapeutics
  developer rather than a software vendor: upstreambio.com is a fourteen-page WordPress marketing
  site, investor material is served from a hosted Q4-style investor-relations subdomain, and the
  company publishes no developer program, no public API, no SDK and no machine-readable API contract.
url: https://raw.githubusercontent.com/api-evangelist/upstream-bio/refs/heads/main/apis.yml
image: https://upstreambio.com/wp-content/uploads/2026/08/upstream-bio-social-image.jpg
x-type: company
x-source: harvest:secondary-market
x-tier: stub
x-tier-reason: harvest
specificationVersion: '0.20'
created: '2026-09-02'
modified: '2026-09-02'
tags:
- Company
- Biotechnology
- Pharmaceuticals
- Life Sciences
- Healthcare
- Immunology
- Respiratory
- Clinical Trials
- Drug Development
- Nasdaq
apis: []
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
- FN: APIs.json
  email: info@apis.io
common:
- type: DomainSecurity
  url: security/upstream-bio-domain-security.yml
- type: Website
  url: https://upstreambio.com/
- type: About
  url: https://upstreambio.com/about/
- type: Blog
  url: https://investors.upstreambio.com/news-events/news-releases
- type: BlogRSS
  url: https://upstreambio.com/feed/
- type: Support
  url: https://investors.upstreambio.com/shareholder-services/contact-us
- type: PrivacyPolicy
  url: https://upstreambio.com/privacy-policy/
- type: TermsOfService
  url: https://upstreambio.com/terms/
- type: LinkedIn
  url: https://www.linkedin.com/company/upstreambio
- type: InvestorRelations
  url: https://investors.upstreambio.com/
- type: LLMsTxt
  url: llms/upstream-bio-llms.txt
x-enrichment:
  date: '2026-09-02'
  status: minimal
  artifacts_added: 3
  pass: local-v1
x-coverage:
  state: none
  reason: not-a-software-company
  detail: >-
    Upstream Bio is a Nasdaq-listed clinical-stage drug developer whose product is a single
    therapeutic program (verekitug, an anti-TSLP-receptor antibody in Phase 2/3); upstreambio.com is
    a fourteen-page WordPress marketing site with no /developers, /docs or /api path at all, the
    investor material lives on a hosted IR subdomain, and the only machine-readable endpoints on
    either host are the CMS defaults — an RSS feed, a Yoast sitemap, and WordPress core's
    undocumented, noindexed /wp-json/ route index — rather than any published product API.
  evidence:
  - url: https://upstreambio.com/
    status: 200
  - url: https://upstreambio.com/openapi.json
    status: 404
  - url: https://upstreambio.com/swagger.json
    status: 404
  - url: https://upstreambio.com/graphql
    status: 404
  - url: https://upstreambio.com/llms.txt
    status: 404
  - url: https://upstreambio.com/.well-known/api-catalog
    status: 404
  - url: https://upstreambio.com/.well-known/agent-card.json
    status: 404
  - url: https://upstreambio.com/.well-known/agent.json
    status: 404
  - url: https://investors.upstreambio.com/llms.txt
    status: 404
  - url: https://investors.upstreambio.com/.well-known/api-catalog
    status: 404
  - url: https://upstreambio.com/wp-json/
    status: 200
  checked: '2026-09-02'