# Zag Bio funding: rounds and investors

> Zag Bio has raised $80M across 1 round since 2025. Investors include T1D Fund, Lightspeed Venture Partners and Polaris Partners. Every round with its source.

Source: https://millionrounds.com/company/zag-bio (Millionrounds; every figure on the page links to its filing or article)

United States · [Series A startup](https://millionrounds.com/companies)

# Who invested in *Zag Bio*

One round we have observed, with the 10 investors named in it. Every figure came from a named source, and where the company reported a raise to the SEC itself, that is shown beside it.

Pharma

Funding summary Updated 26 Oct 2026

**$80M** raised across 1 round since 2025, from 2 sources

- **Latest round:** Series A, $80M Oct 2025
- **Led by:** T1D Fund
- **Investors:** 10 (1 led)

See who backed them

## The rounds

- **Oct 2025** Series A **$80M** [T1D Fund](https://millionrounds.com/fund/t1d-fund) Lead [Lightspeed Venture Partners](https://millionrounds.com/fund/lightspeed-venture-partners) [Polaris Partners](https://millionrounds.com/fund/polaris-partners) [Pear VC](https://millionrounds.com/fund/pear-vc) [Sanofi](https://millionrounds.com/fund/sanofi) [AbbVie](https://millionrounds.com/fund/abbvie) [Mission BioCapital](https://millionrounds.com/fund/mission-biocapital) [KdT Ventures](https://millionrounds.com/fund/kdt-ventures) [Boxer Capital](https://millionrounds.com/fund/boxer-capital) [Regeneron Ventures](https://millionrounds.com/fund/regeneron-ventures) Reported by Firms' own news pages and 1 other

## Everyone who backed them

[T1D Fund](https://millionrounds.com/fund/t1d-fund) Corporate VC **1** round, led 1

[Lightspeed Venture Partners](https://millionrounds.com/fund/lightspeed-venture-partners) VC firm **1** round

[Polaris Partners](https://millionrounds.com/fund/polaris-partners) VC firm **1** round

[Pear VC](https://millionrounds.com/fund/pear-vc) VC firm **1** round

[Sanofi](https://millionrounds.com/fund/sanofi) Investment firm **1** round

[AbbVie](https://millionrounds.com/fund/abbvie) Corporate VC **1** round

[Mission BioCapital](https://millionrounds.com/fund/mission-biocapital) VC firm **1** round

[KdT Ventures](https://millionrounds.com/fund/kdt-ventures) VC firm **1** round

[Boxer Capital](https://millionrounds.com/fund/boxer-capital) VC firm **1** round

[Regeneron Ventures](https://millionrounds.com/fund/regeneron-ventures) Growth equity **1** round

Missing a round, or an investor who was in one? [Tell us](https://millionrounds.com/corrections?slug=zag-bio).

## Quick answers about Zag Bio

### Who invested in Zag Bio?

Zag Bio's investors include T1D Fund, Lightspeed Venture Partners, Polaris Partners, Pear VC and Sanofi, and 5 more on record. T1D Fund led its latest round.

### How much has Zag Bio raised?

Zag Bio has raised $80M across 1 round since 2025.

### When did Zag Bio last raise?

Zag Bio's most recent round was a Series A of $80M in Oct 2025, led by T1D Fund.

### What was Zag Bio's biggest round?

Its most recent round, $80M in Oct 2025, is also its largest on record.

### Who backed Zag Bio first?

Zag Bio's first round on record, in Oct 2025, was backed by T1D Fund, Lightspeed Venture Partners and Polaris Partners and 7 others.

### What stage is Zag Bio at?

Zag Bio's latest named round is a Series A, in Oct 2025.

### Where is Zag Bio based?

Zag Bio is based in the United States.

### Who led Zag Bio's rounds?

T1D Fund led the Series A in 2025.

## Companies like Zag Bio

In the same sector, and raised in the last eighteen months.

[**Matchpoint Therapeutics** $220M · Oct 2026](https://millionrounds.com/company/matchpoint-therapeutics)[**Rx Bandz** Oct 2026](https://millionrounds.com/company/rx-bandz)[**Hera Biotech** $1.8M · Sept 2026](https://millionrounds.com/company/hera-biotech)[**GevRx Nutraceuticals** $300K · Sept 2026](https://millionrounds.com/company/gevrx-nutraceuticals)[**RegCell** $81M · Sept 2026](https://millionrounds.com/company/regcell)[**ClearSight Therapeutics** $307K · Sept 2026](https://millionrounds.com/company/clearsight-therapeutics)

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