Parallel Bio, a trailblazing biotech company based in Cambridge, Massachusetts, has secured $21 million in Series A funding, led by AIX Ventures, with participation from Amplo, Salesforce’s Marc Benioff, and returning investors such as Metaplanet and Humba Ventures. This new round brings the company’s total funding to nearly $30 million and strengthens its mission to accelerate drug discovery by replacing outdated animal models with human immune system replicas grown in the lab.

At the core of Parallel Bio’s breakthrough is its ability to create immune organoids - miniature, fully functional models of human lymph nodes that behave like real immune systems. By integrating advanced tissue engineering, artificial intelligence, and lab automation, Parallel Bio enables drug developers to simulate human immune responses at scale, vastly improving the accuracy and efficiency of preclinical testing.

Why Animal Models Are Holding Us Back

For decades, the pharmaceutical industry has leaned heavily on animal testing to evaluate drug safety and efficacy. Yet, over 95% of drugs that perform well in animals fail in human clinical trials, costing billions of dollars and years of lost time. Parallel Bio’s "immune system in a dish" offers a strikingly better alternative: fully human biology from the start, resulting in faster, safer, and more ethical drug development.

Already, Parallel Bio’s technology is proving its value. The company has partnered with eight pharmaceutical firms, including three Fortune 500 companies, to evaluate more than 50 drug candidates. Centivax, for example, successfully used the platform to complete preclinical studies for a universal flu vaccine - a compelling proof of concept for the future of vaccine and immunotherapy development.

Blending Biology and AI for Faster Answers

The strength of Parallel Bio’s platform lies in its fusion of biological realism and computational power. Their organoids replicate critical immune functions, while AI and robotic automation enable large-scale analysis of immune responses across thousands of models. This combination empowers researchers to predict patient-specific outcomes and fine-tune therapies much earlier than traditional approaches ever allowed.

And here’s where founders can draw a critical lesson: Parallel Bio didn’t just make incremental improvements on an old system; they completely reimagined it. They asked, “What if we didn’t have to use animals at all?” That shift unlocked an entirely new market and eliminated a constraint that everyone else had simply accepted. For entrepreneurs in any field, this illustrates a profound insight: the biggest breakthroughs often come from questioning what others assume is impossible or “just the way things are.” By focusing on fundamental constraints - not surface-level fixes - founders can create products and platforms that make existing categories obsolete.

Scaling Toward Human-First Drug Development

The $21 million Series A funding will allow Parallel Bio to expand its AI and automation capabilities, grow its scientific teams, and accelerate partnerships with pharmaceutical companies worldwide. The ultimate goal is to integrate human immune system organoids into mainstream drug development pipelines, replacing animal testing with more predictive, scalable, and ethical models.

Parallel Bio estimates that its platform can reduce drug development timelines by up to nine years and slash costs by as much as $2 billion per candidate. These are not small incremental savings; they represent a total reimagining of how new medicines can reach patients faster and with far fewer failures.

A Leadership Team Built for Disruption

Founded in 2021 by Robert DiFazio and Juliana Hilliard, Parallel Bio’s leadership combines deep expertise in immunology, bioengineering, and data science. Their vision is not simply to build a new tool but to redefine the entire foundation of how human biology is used in drug discovery. With support from high-profile investors such as Marc Benioff and institutional partners, the team is well-positioned to scale this transformative approach globally.

Transforming the Future of Health

Parallel Bio’s technology also holds potential far beyond preclinical drug development. By modeling immune responses in diverse patient groups, the platform can inform personalized medicine strategies, improve vaccine design, and help predict population-level responses to emerging pathogens. In an era of global health uncertainty and rising demand for faster treatments, this kind of predictive, human-first approach is poised to become indispensable.

As more companies and regulators recognize the limitations of animal models, Parallel Bio’s human immune system organoids could set a new gold standard for safety and efficacy testing. Their platform offers a compelling alternative: a data-rich, ethically sound, and far more accurate foundation for therapeutic innovation.

The company’s Series A raise is more than just a capital injection; it’s a powerful validation of a fundamentally new way to approach life sciences. By daring to ask "why not?" and dismantling a century-old reliance on animal models, Parallel Bio is not only accelerating drug discovery but also changing the very definition of what is possible in biotech.