Avenue Biosciences, a Palo Alto-based protein engineering technology company, has raised $5.7 million in seed extension funding to scale a high-throughput platform designed to measure and modulate the protein secretory pathway, a core cellular process responsible for folding, modifying, and secreting therapeutic proteins.
The round was co-led by Balnord and Tesi, with participation from existing investors Voima Ventures, Inventure, the University of Helsinki, and Dimerent. Avenue said the financing brings its total funding raised since 2024 to $8.7 million.
Avenue’s platform focuses on a common bottleneck in biologics development and production: the ability of cells to efficiently produce complex therapeutic proteins at high yield and consistent quality. The company’s approach uses a library of thousands of naturally occurring and engineered signal peptides—short sequences intrinsic to proteins that help direct newly made proteins into the secretory pathway—to measure how efficiently a given therapeutic protein is produced and to tune manufacturing performance.
By testing large numbers of signal peptide variants at high throughput, Avenue aims to generate thousands of versions of a therapeutic protein and identify combinations that improve manufacturability. The company positions the platform as a way to outperform conventional approaches that typically rely on a limited set of widely used signal peptides, particularly as modern therapeutics grow more complex, including multispecific antibodies and other advanced protein formats.
Avenue said the technology can help make complex and emerging modalities more manufacturable, spanning antibodies, vaccines, AI-designed proteins, and gene therapies. The company also highlighted applications in enabling therapeutic targets that may otherwise be difficult to produce at scale, including programs in oncology, infectious disease, and immunology.
The company also emphasized that signal peptides are removed from the mature protein, meaning the end therapeutic target can remain essentially the same as the original, a feature Avenue said could make the approach useful in the manufacturing of biosimilars, where maintaining comparability is critical while improving efficiency and cost.
In addition to the wet-lab screening component, Avenue said its platform generates large datasets linking specific signal peptides with specific protein targets, which it expects to use to build prediction tools for therapeutic developers. Investors backing the company pointed to the potential for combining experimental data with machine learning to create higher-quality models that can reduce trial-and-error in manufacturing development.
Avenue’s technology originated from research conducted at the University of Helsinki in Finland, including work in the Ville Paavilainen laboratory, and the company noted an operational footprint that includes a Helsinki laboratory site.
KEY QUOTES:
“The secretory pathway is one of the remaining black boxes in therapeutic protein production. Despite its importance, the current industry standard relies heavily on a decades-old playbook, testing only a small set of safe signal peptides rather than exploring thousands of sequence variants. Our technology makes the increasingly complex proteins, such as AI-designed proteins or multispecifics, more manufacturable, improving access to lifesaving therapies.”
Tero-Pekka Alastalo, CEO and Co-founder, Avenue Biosciences
“Novel protein-based biologics under development, for example, in cancer, rare diseases, or immunology, are becoming increasingly targeted and effective, performing several functions with one therapeutic component: bringing immune cells to the right place, activating them, and recognizing disease cells more specifically. However, this adds complexity to the protein structure, adding manufacturing cost, or in the worst case, preventing the development completely.”
Katja Rosti, COO, Co-founder, and Helsinki Laboratory Site Lead, Avenue Biosciences
“Avenue’s technology taps into some of the largest opportunities in biotech right now: it significantly lowers the costs of biologics and transforms therapeutic protein manufacturing with the use of AI. Their combination of wet lab and machine learning enables the development of high-quality prediction tools for therapeutic developers, targeting the biggest bottlenecks in the industry. The team has shown incredible execution, with really strong industry names as their clients.”
Gabriele Poteliunaite, Investor, Balnord
“Many life-altering therapeutic innovations remain out of reach for most of the global population. We see significant growth opportunities for Avenue’s technology, which is deeply rooted in Finnish scientific discovery, and has the potential to become a gold standard in its field.”
Miia Kaye, Investment Director, Tesi
