# Mariana Oncology

Source: https://onco.cc/companies/mariana-oncology/  
OnCo record `mariana-oncology` (Company). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)"; commercial use needs a licence.

## TL;DR

Mariana Oncology designs small protein fragments that carry a radioactive isotope to tumours, starting with small cell lung cancer. Novartis bought the company in 2024 for 1 billion dollars up front.

## Summary

Mariana Oncology, founded in 2021 in Watertown, Massachusetts by Atlas Venture, Access Biotechnology and RA Capital Management, built a fully integrated radiopharmaceutical platform combining peptide discovery, radiochemistry, in-house GMP manufacturing, isotope supply and formulations to extend product shelf life. Its portfolio of peptide-based radioligand therapies addresses a range of solid tumours; the lead candidate MC-339 is a radioligand therapy for small cell lung cancer that was expected to enter the clinic in 2024. The company closed a USD 175 million Series B in September 2023 co-led by Deep Track Capital and Forbion, and in May 2024 agreed to be acquired by Novartis for USD 1 billion upfront and up to USD 750 million in milestones. As a Novartis company it announced a USD 50 million expansion of radioligand R&D facilities in June 2025.

## Fields

- Kind: Company
- Last checked: 2026-09-10
- HQ: Watertown, MA
- Type: radiopharma
- Website: https://marianaoncology.com/

## Notes

- MC-339 target not stated on fetched pages. Series A not fetched and omitted.

## Sources

- Official website: https://marianaoncology.com/
- Series B press release: https://marianaoncology.com/news/mariana-oncology-announces-usd175-million-series-b-financing/
- Novartis acquisition announcement: https://marianaoncology.com/news/mariana-oncology-to-be-acquired-by-novartis-to-advance-precision-radiopharmaceuticals-to-treat-cancer/

## Connected records

- cancers: [Small-cell lung cancer](https://onco.cc/cancers/sclc/)
- fronts: [Radiopharmaceuticals & Theranostics](https://onco.cc/fronts/radiopharma/)
- technologies: [Radioligand therapy (beta emitters)](https://onco.cc/technologies/radioligand-therapy/)
- companies: [Atlas Venture](https://onco.cc/companies/atlas-venture/), [Forbion](https://onco.cc/companies/forbion/), [Novartis](https://onco.cc/companies/novartis/), [RA Capital Management](https://onco.cc/companies/ra-capital/)

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JSON: https://onco.cc/api/v1/entities/mariana-oncology.json