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A new, big, bold idea to fight cancer


The fight against cancer needs new, big, bold ideas. At Siren, we’ve got one: Universal AAV Immuno-Gene Therapy™.

We are combining two transformative therapeutic technologies – AAV gene therapy and cytokine immunotherapy – into a single, reimagined modality that overcomes key challenges and redefines how we destroy tumor cells and elicit anti-tumor immunity.

How AAV immuno-gene therapy works


We deliver vectorized, engineered cytokines directly to the tumor.

Our low-dosed gene therapy is precisely infused directly into the tumor, avoiding healthy cells.


Endogenous targeted cytokine expression rapidly kills tumor cells.

Our therapy destroys tumor cells in both resected and unresected tumors, including lingering tumor cells that are the primary culprit for recurrence in many cancers.


Cytokine expression supercharges the innate immune response.

Release of inflammatory cytokines from the infusion site activates the innate immune response by activating macrophages and recruiting natural killer cells.


Antigens can further activate the adaptive immune response.

Release of tumor and AAV capsid antigens from the dying tumor can activate an adaptive immune response by recruiting cytotoxic T lymphocytes.

The Result

Our attack on cancer is swift, precise, and comprehensive

Our name, Siren Biotechnology, was inspired by the powerful signal our AAV immuno-gene therapy sends to the immune system, stimulating an immediate anti-tumor response.

We’re sounding the alarm against cancer!

Our approach is universal

This is the first AAV gene therapy that can be made once and used in numerous indications – a huge leap forward for the field.

Our universal design drastically reduces clinical development times, manufacturing timelines, and capital needs for each clinical trial.

Most importantly, ‘universal’ means countless solid tumor cancer patients – regardless of tumor type or mutations – may benefit from this breakthrough approach.

We redefine cytokine immunotherapy

Cytokines play a key role in recruiting and activating immune cells and are an ideal tool for immunotherapy.

But significant challenges have prevented cytokine immunotherapy from realizing its cancer-fighting potential … until Siren, that is.

The Challenge
Cytokines have profoundly short half-lives, resulting in transient or no clinical benefit.
The Solution
By vectorizing cytokines, we enable durable, steady, efficacious cytokine expression.
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We ensure unparalleled safety

Multiple layers of safety differentiate our approach from other cytokine immunotherapy and AAV gene therapy approaches.


Local delivery to the tumor only requires low-doses of AAV, drastically reducing the chance of both local and systemic toxicities.

Self-Limiting Payload Activity

As tumor cells die, vectorized cytokine payload activity immediately ceases as AAV genomes don’t survive cell death events.

Immunologically Optimized

The entire AAV genome has been immunologically optimized to limit non-specific immune system activation.

Not Impacted by Anti-AAV Immunity

Our approach is not impacted by the widespread pre-existing anti-AAV immunity seen with systemically administered AAV gene therapies.

Vector Integrity Optimized

Our production process is optimized for vector integrity, minimizing immunogenic empty capsids, genomic fragments, and viral componentry.

Optimal Delivery Modality

The same characteristics that make AAV an ideal vector for rare diseases make it an ideal vector for cancer. AAV is safe, non-lytic, non-replicative, non-pathogenic, and clinically validated.
Universal AAV Immuno-Gene Therapy. It's Here.