# Martijn Kleijwegt

> Martijn Kleijwegt is a Series A investor at OxThera backing Biotechnology and Pharmaceutical. See 9 investments, check sizes, portfolio. Updated Aug 2026.

- Type: Angel Investor
- Fund: [OxThera](https://shizune.co/investors/profile/oxthera)
- Location: Amsterdam, The Netherlands
- Total investments: 9
- Last investment: Sep 2024
- Lead investor: 67%
- Last updated: Aug 2026
- LinkedIn: http://www.linkedin.com/pub/martijn-kleijwegt/10/861/262

Martijn Kleijwegt is a Series A investor at OxThera in Amsterdam focused on Biotechnology and Pharmaceutical. Martijn Kleijwegt became a member Prosensa’s supervisory board in 2008. He founded Life Sciences Partners in 1998 and has been managing partner of Life Sciences Partners since then. He has served on the boards of a number of companies including Qiagen, Rhein Biotech, Crucell, Movetis and Pronota. He graduated from the University of Amsterdamwith a degree in economics.

## Investment focus

### Industry

| Industry | Investments | Share |
| --- | --- | --- |
| Biotechnology | 5 | 56% |
| Pharmaceutical | 4 | 44% |
| Medical | 3 | 33% |
| Genetics | 3 | 33% |
| Health Care | 3 | 33% |

10 industries tracked in total.

### Stage

| Stage | Investments | Share |
| --- | --- | --- |
| Series A | 3 | 33% |
| Funding Round | 3 | 33% |
| Series B | 1 | 11% |
| Series C | 1 | 11% |
| Series F | 1 | 11% |

### Country

| Country | Investments | Share |
| --- | --- | --- |
| The Netherlands | 3 | 33% |
| Belgium | 2 | 22% |
| Denmark | 1 | 11% |
| United States | 1 | 11% |

## Investments

| Company | Description | Amount | Stage | Date | Website |
| --- | --- | --- | --- | --- | --- |
| PanTera | PanTera focuses on the large-scale production of actinium-225, a promising radioisotope for targeted cancer therapies. The company aims to improve accessibility to personalized nuclear medicine treatments while ensuring sustainability through the recycling of materials in their production process. | $110.3M | Series A | Sep 11, 2024 |  |
| Vico Therapeutics | Vico Therapeutics is a developer of ribonucleic acid (RNA) modulating therapies for rare neurological disorders. The company discovers, develops, and delivers therapies for CNS disorders. Its initial focus is on SCA which is a subgroup of hereditary ataxia, HD which is a neurodegenerative disorder, and RTT-a neurodevelopmental disorder primarilyaffecting girls that enable clients with providing therapy for it.Vico Therapeutics was founded in 2019 by Luc Dochez, Josh Mandel-Brehm, Judith van Deutekom, and Gail Mandel and it is headquartered in Leiden, The Netherlands. | $72.1M | Series B | Jan 05, 2024 |  |
| Vico Therapeutics | Vico Therapeutics is a developer of ribonucleic acid (RNA) modulating therapies for rare neurological disorders. The company discovers, develops, and delivers therapies for CNS disorders. Its initial focus is on SCA which is a subgroup of hereditary ataxia, HD which is a neurodegenerative disorder, and RTT-a neurodevelopmental disorder primarilyaffecting girls that enable clients with providing therapy for it.Vico Therapeutics was founded in 2019 by Luc Dochez, Josh Mandel-Brehm, Judith van Deutekom, and Gail Mandel and it is headquartered in Leiden, The Netherlands. | $31M | Series A | Jul 29, 2020 |  |
| AM Pharma | AM-Pharma B.V., a biopharmaceutical company, engages in the development and commercialization of therapeutics for human use in the Netherlands. It focuses in the pre-clinical and clinical development of novel therapeutics to treat inflammatory and infectious diseases. The company develops products based on endogenous proteins and protein derivedpeptides, as well as molecules that naturally occur in the human body. Its products include alkaline phosphatase for treatment of acute kidney injury and ulcerative colitis; and immune response amplifying peptide hLF1-11 for the treatment of drug resistant hospital acquired infections. The company was founded in 2000 and is headquartered in Bunnik, the Netherlands. | $127.3M | Series F | Jul 16, 2019 |  |
| Eloxx | Eloxx Pharmaceuticals based in Israel is a Pontifax portfolio company established in 2013 by Dr. Silvia Noiman, that serves as its Executive Chairman and Dr. Shmuel Tuvia. The company, is a biopharmaceutical company focused on discovery, development and commercialization of compounds for the treatment of genetic diseases caused by nonsensemutations including: Cystic fibrosis, Duchene Muscular Dystrophy, Usher syndrome, Ataxia-telangiectasia, Beta thalassemia, Tay-Sachs Hurler syndrome and many others.Eloxx Pharmaceuticals approach and knowhow allows moving rapidly from target drugs discovery program to clinical drug candidates. Building a robust pipeline of molecules designed for an array of nonsense genetic diseases. Translation of mRNA to a protein is the event where the cellular machinery, i.e. ribosome, ultimately dictates the quantity and timing for each protein to be produced. Thus, molecules that induce ribosomal readthrough overcome the nonsense mutations and allow production of a full-length functional protein. These molecules hold great therapeutic potential for the treatment of many genetic diseases. | $8M | Series C | Aug 02, 2017 |  |
| Orphazyme | Orphazyme develops innovative new therapies for the treatment of a family of serious genetic disordes called lysosomal storage diseases, and is based on discoveries emerging from the academic laboratory of its scientific founders: Professor Marja Jäättela and Thomas Kirkegaard Jensen from the Danish Cancer Society (Kræftens Bekæmpelse).Orphazyme is based in Copenhagen and has established collaborations with top-tier academic institutions in Europe and USA. | $15.4M |  | Mar 08, 2017 |  |
| Prosensa | Prosensa is a biotech company also known as Ribpharm Inc dedicated to the commercialization of products for the healthcare market based on RNA-based therapeutics.During the development of this technology, it became clear that many opportunities exist for the development of these products into novel commercially attractive products. Theseproducts are mainly in the field of genetic disorders, anti-infectives and oncology.Prosensa will focus to maximize the commercial development of the current program, and take advantage of the large novel market opportunities supported by a strong IP position. Prosensa will initially operate mainly as a focussed company, outsourcing most of its activities to specialized organizations. | $25.2M |  | Jan 25, 2012 |  |
| Prosensa | Prosensa is a biotech company also known as Ribpharm Inc dedicated to the commercialization of products for the healthcare market based on RNA-based therapeutics.During the development of this technology, it became clear that many opportunities exist for the development of these products into novel commercially attractive products. Theseproducts are mainly in the field of genetic disorders, anti-infectives and oncology.Prosensa will focus to maximize the commercial development of the current program, and take advantage of the large novel market opportunities supported by a strong IP position. Prosensa will initially operate mainly as a focussed company, outsourcing most of its activities to specialized organizations. | $18M | Series A | Feb 01, 2007 |  |
| ActoGeniX | ActoGeniX is a biopharmaceutical company focused on the development and commercialization of a range of biological drugs. ActoGeniX was founded by Bernard Coulie and Mark Vaeck in 2006 and is based in Zwijnaarde, Belgium. |  |  |  |  |

9 of 9 investments shown.

## Co-investors
- [Kurma Partners](https://shizune.co/investors/profile/kurma-life-science-partners) — VC Fund, 7 deals together
- [Idinvest Partners](https://shizune.co/investors/profile/idinvest-partners) — VC Fund, 3 deals together
- [Pureos Bioventures](https://shizune.co/investors/profile/pureos-bioventures) — VC Fund, 3 deals together
- [Abingworth](https://shizune.co/investors/profile/abingworth-management) — VC Fund, 2 deals together
- [Ackermans & van Haaren](https://shizune.co/investors/profile/ackermans-van-haaren) — VC Fund, 2 deals together
- [Droia Ventures](https://shizune.co/investors/profile/droia) — VC Fund, 2 deals together

## About OxThera

VC Fund · Stockholm, Sweden

OxThera is a biopharmaceutical company with products in late stage clinical development focusing on Primary and Secondary Hyperoxaluria. OxThera’s intellectual property includes worldwide patents for compositions and treatment of hyperoxaluria with bacteria, and enzymes. Oxabact® holds Orphan Drug designations in Europe and in the US for thetreatment of primary hyperoxaluria.

3 contacts available at OxThera.

| Name | Title | Profile |
| --- | --- | --- |
| Hugo Petit | Chief Financial Officer | https://shizune.co/investors/profile/hugo-petit |
| Martijn Kleijwegt | Director | https://shizune.co/investors/profile/martijn-kleijwegt |
| Matthew Gantz | Chief Executive Officer | https://shizune.co/investors/profile/matthew-gantz |

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## FAQ

### What does Martijn Kleijwegt invest in?

Martijn Kleijwegt invests primarily in Biotechnology, Pharmaceutical and Medical startups, most often at Series A and Funding Round stage. Most of the 9 investments tracked by Shizune back companies in The Netherlands. The Investment Focus section breaks down every industry, stage and country in the portfolio.

### When did Martijn Kleijwegt last invest?

The most recent investment recorded for Martijn Kleijwegt closed in Sep 2024. Shizune tracks 9 investments in total for this profile, including round sizes, stages and portfolio companies, all sourced from confirmed public funding rounds and refreshed monthly.

### Is Shizune's investor data accurate?

Yes — every stat on this profile is calculated from confirmed public funding rounds monitored across hundreds of sources since 2020. This profile was last refreshed in Aug 2026 and is updated monthly. Spotted something off? Use the “Suggest an edit” link near the top of the page.

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