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A New Class of Therapeutics

Innovating with Novel Genetic
Engineering Platforms

Poseida Therapeutics is advancing a new class of cell and gene therapies we believe have the capacity to cure certain cancers and rare diseases by leveraging our proprietary genetic engineering platforms.

We utilize our novel gene insertion and gene editing technologies to introduce or edit genes, which may enable our therapies to treat a range of cancers and rare diseases. Our proprietary, differentiated tools lay the foundation for potentially safer and more effective treatments.

A blue icon of a segment of DNA. A bracket surrounds it with an orange arrow pointing towards a gene.

INSERTION PiggyBac Platform

The piggyBac transposon is a cut-and-paste gene insertion platform that can stably integrate DNA into the genome. This is enabled by a high efficiency transposase which accommodates a large DNA cargo. We have developed an optimized piggyBac transposase as an enhanced proprietary system we call Super piggyBac.

Our piggyBac DNA delivery system efficiently delivers genetic cargo into both resting and activated/dividing cells. During the CAR-T manufacture process, it preferentially modifies naïve T cells and stem cell memory T cells (Tscm), thereby creating products enriched for an early memory phenotype.

Our data suggest that piggyBac is ideal for introducing therapeutic DNA transgenes to growing tissues, such as the juvenile liver. Therapies created with piggyBac offer a potentially more consistent and durable treatment response.

PiggyBac can deliver genetic payloads to a wide variety of cell types (in vivo or ex vivo), including immune cells and hepatocytes, resulting in durable transgene expression. As demonstrated in T cells, piggyBac can easily carry multiple targeting genes like CARs and/or a TCR, a gene encoding a safety switch, and a selection gene – all without the need for viral-based transgene delivery.

A scientific illustration shows the steps of gene insertion using a piggyBac transposon to paste a cargo transgene into the genome.
A blue icon of a segment of DNA. A short region of base pairs is colored orange.


Cas-CLOVER is a high-fidelity, proprietary gene editing technology with low to no off-target activity. Cas-CLOVER utilizes a deactivated Cas9 (dCas9) that acts as a binding protein when combined with a guide RNA. Rather than cutting the DNA, the dCas9 guides a fused nuclease domain from the Clo051 enzyme (CLOVER), which can only cut DNA when bound to its matching pair, giving it enhanced fidelity via a highly specific molecular address.

Cas-CLOVER is effective in resting T cells, which helps preserve an early T cell memory phenotype, and is capable of making multiple gene edits in the same cells. Advantages of Cas-CLOVER include ease of design in cell therapy, lower cost, and multiplexing capabilities.

A scientific illustration shows a guide RNA directing a dCas9 molecule to bind a segment of DNA. An adjoining Clo051 molecule is paired with a matching mirror of Clo051, dCas9, and guide RNA to show how Poseida’s technology makes specific genetic cuts.
A blue icon of a CAR-T cell.

DELIVERY Leading Gene Delivery Systems

We have multiple gene delivery technology platforms, including AAV plus nanoparticles and fully non-viral nanoparticles, which can deliver large genetic material to multiple cell types in vivo or ex vivo.

We aim to match the right tools and cargo with the right delivery mechanism for each indication to achieve long-term, durable gene expression – with the goal of developing effective, potentially functional cures.

A blue hexagonal AAV icon with a coil of yellow DNA inside. A simple blue icon of a cell with a segment of navy blue RNA inside. A simple blue icon of a cell with a segment of yellow DNA inside.
A light blue icon of a health plus sign with a yellow check mark in the center.

BENEFITS Additional Benefits in Cell Therapy

TSCM Cells

At Poseida, our allogeneic, or off-the-shelf, CAR-T products are produced with a high percentage of desirable TSCM cells, or stem cell memory T cells. These cells are long-lived, self-renewing, and capable of differentiating into the entire spectrum of T cell subsets primed to lead the effector response against the cancer. Data have shown that TSCM cells can survive for years after CAR-T treatment, potentially providing durable anti-tumor protection.

A schematic showing T cell differentiation with a light blue cell at the top representing an undifferentiated stem cell memory T cell. Colored lines pointing downwards show transition to a slightly differentiated grey central memory cell, then an intermediate blue effector memory cell, and finally a fully differentiated yellow effector T cell.

CAR-T Tools
Poseida’s platforms enable a revolutionary new class of CAR-T therapies

Poseida's platforms enable a revolutionary new class of CAR-T therapies, showcased by a target icon for precise and multiple genetic edits, a rocket ship icon for our proprietary Booster Molecule that improves manufacturing performance, a toggle icon for our safety switch technology to selectively eliminate CAR-T cells in the patient if necessary, a shield for armoring with cytokines and pro-inflammatory elements to improve efficacy, and a cell icon for a final product containing only modified CAR-T cells.

Unique to Poseida
Our platforms offer large cargo capacity and precise gene editing, with the potential for stable, long-term gene expression. Engineered to provide potentially better tolerability, maximal potency, targeted delivery, and expression in diverse cell types, we believe Poseida’s therapeutic candidates offer the capacity to cure cancer and genetic diseases.