#27-Cell and Gene Therapy Today
Stay up to date with the latest developments in your field with our weekly digest of industry news and research articles.
I’m Pedro Silva Couto, and this is Cell and Gene Therapy Today. Here I will be sharing of the most recent news in CGT field as well as summarising research articles focused on translational research, manufacturing and clinical studies featuring cell and gene therapy product candidates.
CGT News this week:
💰 Plasticell, CGT Catapult, and Imperial College London secure £800k to develop a scalable manufacturing platform for allogeneic cell immunotherapies (news here). This project will be focused on establishing a scalable manufacturing platform for allogeneic CAR-NK therapies using iPSCs as starting material.
📈 Astellas Pharma invests $50 Million to support Poseida Therapeutics' allogeneic CAR-T cell therapy for solid tumours (news here). Poseida’s lead candidates are P-MUC1C-ALLO1 in the allogeneic space (targetting the Mucin 1 protein), a BCMA CAR-T product and a dual target product (for CD19 and CD20) for the autologous space in collaboration with Roche.
📈 GenScript expands RNA/DNA manufacturing capabilities for CGT demand in Zhenjiang, China (news here). GenScript Biotech has increased its manufacturing capacity by 400,000 square feet in Zhenjiang, China, focusing on providing CRISPR-based solutions for gene and cell therapy to accelerate clinical studies in the field
🤝 WuXi ATU and GeneMedicine to collaborate for oncolytic virus product development and manufacturing (news here). The Korean company now has several oncolytic adenovirus candidates in its pipeline to be delivered intratumorally or intravenously in patients suffering from solid tumours such as pancreatic, lung or liver cancer.
🤝 Evox Therapeutics teams up with Icahn Mount Sinai to prioritize the treatment of heart diseases with extracellular vesicle-AAV encapsulated gene therapy (news here). In addition to the EV-AAV product, the Oxford-based company has several other candidates in the pipeline, such as mRNA-based, in partnership with Takeda, and siRNA in collaboration with Elly Lilly.
CGT Research this week:
Non-viral CAR-T application for solid tumours
Clinical study featuring mRNA-based anti-cMET CAR-T deemed safe but efficacy fails to impress in patients sufferent from melanoma or triple negative breast cancer (N=7) (study here).
This study reports on the findings of phase 1 clinical trial (NCT03060356) that evaluated the safety and efficacy profile of a non-viral CAR-T product delivered intravenously (1x108 T cells/dose) to patients diagnosed with solid tumours without lymphodepletion chemotherapy. The authors have put forward this target (cMET) given its substantial expression on melanoma and triple-negative breast cancer and limited expression on other tissues. The decision to deliver the CAR construct in a mRNA format was based on the lower risk of off-tumour toxicities. Regarding the product’s safety profile, no patients developed grade 3 or higher toxicities. Although the safety profile seemed satisfactory, the efficacy reported was limited, with no patient reporting partial or complete responses. Stable disease was reported in 4 patients where disease progression cases totalled three individuals at the 25-day assessment time point. The authors put forward poor expansion, limited trafficking and infiltration of the CAR-T cells as potential causes for the low efficacy observed. Moreover, the manuscript speculates that clinical activity could be maximized, providing a durable CAR construct was used. The manufacturing process followed by the authors started with T cell isolation from a leukapheresis product using a CaridianBCT Elutra. The CD3 populations were then expanded in XVIVO-15 and activated with CD3/CD28 dynabeads. The seed train lasted for 5 days, and a Wave bioreactor was chosen to conduct 4 additional days of expansion. Given the transient nature of transfection processes using mRNA, electroporation was conducted at the end of the process using a Maxcyte GT flow. Before cell storage in an infusable cryopreservation medium, the final product was kept for 4 hours in a recovery medium after the electroporation was delivered.
hMSCs for critical limb ischaemia-phase one clinical trial
Clinical study featuring a placenta-derived hMSC product demonstrated safe and potentially associated with reduced risk of amputation in patients suffering from critical limb ischaemia (N=9) (study here).
This study reports on the findings of phase 1 clinical trial (IRCT20210221050446N1) where the authors investigated the safety and efficacy profile of two dosages of placenta-hMSCs delivered intramuscularly (20x106 and 60x106). The product was deemed safe as no major adverse events were reported after infusion and throughout the study including no change in T-cell subsets and TNF-α concentration between the baseline and the 6-month evaluation period. This study reported efficacy in several metrics related to physical function and rest pain. However, it should be mentioned that this study did not show the generation of new blood vessels between baseline and follow-up, which suggests the limited role of the product in promoting angiogenesis. Given that IL-1 and IFN-γ decreased during the study, the authors hypothesised hMSCs may act primarily as regulators of the inflammatory response in patients with CLI. It should be mentioned that previous in vivo studies focused on using VEGF-transduced hMSCs have demonstrated improved blood flow in a critical limb ischaemia context The manufacturing process used to produce the placenta-derived hMSC product started with placenta digestion using a collagenase at a concentration of 1 mg/mL for three hours. After centrifugation, the cells were expanded in a medium formulation containing FBS. It becomes unclear how many doublings the cells experienced before being suspended in PBS and albumin and administered to the patients. This product was manufactured and administered fresh with no cryopreservation being performed.
CAR-T for solid tumours: in vivo studies
Study demonstrates anti-tumor effect and tumor infiltration capacibilities of CD24 CAR-T product in a triple negative breast cancer in vivo model (study here).
In this study, the authors started by exploring the role of the CD24 receptor given that its expression was related to the worst survival in patients suffering from breast cancer. Then the in vitro anti-tumour activity against cancer cells was demonstrated. In addition, increased IL-2 and IFN-γ expression in the presence of tumour cells was also detected when compared to non-transduced CD3. Finally, this study demonstrated specific in vivo cytotoxicity showing superior infiltration capabilities again when compared to the control group and producing higher levels of gramzyme b and IFN-γ. The manufacturing process of this CAR-T product included the following sections: LV manufacturing, CAR-T manufacturing. Transgene, packaging and envelope plasmids were added to HEK293 in a ratio of 4:2:1 in the presence of EZ Trans. LV collection was performed a 24 and 48 hours post-transfection, filtered with a 0.45-μm filter and centrifuged at 20,000 × g for 120 min. CAR manufacturing started with CD3 isolation from PBMCs using a magnetic column and was activated using CD3/CD28 Dyna beads. After the 2-day activation period, the cells were expanded in RPMI supplemented with 10% FBS and 100 IU/mL of IL-2. Transduction was performed at an MOI of 10 using 6 μg/mL polybrene at the 24-well plate scale using a 90 min centrifugation cycle at 1200g. The expansion step lasted for five days and used a similar medium formulation but with 300 IU/mL of IL-2.
This is it for this week’s Cell and Gene Therapy Today, which I aim to send you every Wednesday. If you found it valuable, please feel free to sign-up or consider sending it to someone who finds this content useful!
I am currently a post-doctoral researcher at the University College London, and my project is focused on scalable CAR-T cell manufacturing using non-viral methods. You can find more about my research on my Google Scholar or my LinkedIn page.
Last but not least, this content was only possible to produce with the sponsorship of celltrials.org, the leading online portal tracking the clinical trial landscape of cell and gene therapy products. They have data packages on CAR-T, hMSCs, Extracellular Vesicles, and Cell-Free products, as well as in vivo gene therapy products (visit celltrials.org).