# Sionna Therapeutics funding: rounds and investors

> Sionna Therapeutics has raised $182M across 1 round since 2024. Investors include Atlas Venture, OrbiMed and RA Capital Management. Every round with its source.

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

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

# Who invested in *Sionna Therapeutics*

One round we have observed, with the 4 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.

Biotech

Funding summary Updated 26 Oct 2026

**$182M** raised across 1 round since 2024, from 1 source

- **Latest round:** Series C, $182M Mar 2024
- **Investors:** 4

See who backed them

## The rounds

- **Mar 2024** Series C **$182M** [Atlas Venture](https://millionrounds.com/fund/atlas-venture) [OrbiMed](https://millionrounds.com/fund/orbimed) [RA Capital Management](https://millionrounds.com/fund/ra-capital-management) [Perceptive Advisors](https://millionrounds.com/fund/perceptive-advisors) Source recorded

## Founders and team

From Sionna Therapeutics's own website: 6 on the team.

- **Mike Cloonan** President and Chief Executive Officer
- **Andy Chu** Vice President, Information and Technology
- **Erica Iorio** Vice President, Finance and Controller
- **Jen Fitzpatrick** Chief Legal Officer & Head of Program Management
- **Laurie Stelzer** Director
- **Paul Clancy** Chair

## Everyone who backed them

[Atlas Venture](https://millionrounds.com/fund/atlas-venture) VC firm **1** round

[OrbiMed](https://millionrounds.com/fund/orbimed) Private equity **1** round

[RA Capital Management](https://millionrounds.com/fund/ra-capital-management) Private equity **1** round

[Perceptive Advisors](https://millionrounds.com/fund/perceptive-advisors) Asset manager **1** round

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

## Quick answers about Sionna Therapeutics

### Who invested in Sionna Therapeutics?

Sionna Therapeutics's investors include Atlas Venture, OrbiMed, RA Capital Management and Perceptive Advisors.

### How much has Sionna Therapeutics raised?

Sionna Therapeutics has raised $182M across 1 round since 2024.

### When did Sionna Therapeutics last raise?

Sionna Therapeutics's most recent round was a Series C of $182M in Mar 2024.

### What was Sionna Therapeutics's biggest round?

Its most recent round, $182M in Mar 2024, is also its largest on record.

### Who backed Sionna Therapeutics first?

Sionna Therapeutics's first round on record, in Mar 2024, was backed by Atlas Venture, OrbiMed and RA Capital Management and 1 others.

### What stage is Sionna Therapeutics at?

Sionna Therapeutics's latest named round is a Series C, in Mar 2024.

### Where is Sionna Therapeutics based?

Sionna Therapeutics is based in the United States.

## Companies like Sionna Therapeutics

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

[**Star Therapeutics** $325M · Oct 2026](https://millionrounds.com/company/star-therapeutics)[**Promaxo** $106M · Oct 2026](https://millionrounds.com/company/promaxo)[**Prolific Machines** $105M · Oct 2026](https://millionrounds.com/company/prolific-machines)[**IMIO** $19M · Oct 2026](https://millionrounds.com/company/imio)[**Clinical Ink** $24M · Oct 2026](https://millionrounds.com/company/clinical-ink)[**Rejuvenate Bio** $13M · Oct 2026](https://millionrounds.com/company/rejuvenate-bio)

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