Welcome to your deal review for the month of September. There was some healthy news flow around cell-based immunotherapy companies this past month, heating up a space that is already ablaze with activity. Undoubtedly the company that took the spotlight was Adaptimmune, which completed a venture capital (VC) round of over $100 million! The money will take the company deep into clinical development and puts a fire under other companies in pursuit of similar technologies. Read on to find out more.
In a deal led by New Enterprise Associates, and supported by 10 additional VC groups, Oxford-based Adaptimmune has completed a $104 million series A round to fund its engineered T-cell technology. The approach is similar to that of chimeric antigen receptor (CAR) T-cells, where T cells are modified to express a receptor that targets cancer cells. Adaptimmune claims its Affinity Enhanced T cell receptor (TCR) technology is ultimately more flexible than the CAR-T approach under development by several academic groups and companies in industry, namely Novartis and Juno Therapeutics, by allowing for the generation of T cells that can target not just surface proteins, but intracellular targets as well. CAR-T cells, which are designed to have antibody fragments on their surface that recognize peptides expressed by cancer cells, are limited by the number of antibodies that can be used to re-direct the T cell to the cancer cell as the majority of cancer targets (~80%) are intracellular.
NeoStem (NBS) announced the licensing of a patent portfolio from The Rockefeller University to expand and protect its intellectual property (IP) position in the area of using dendritic cells for the purpose of eliciting immune responses targeted to cancer cells. The patents are entitled “Methods for use of Apoptotic Cells to Deliver Antigen to Dendritic Cells for Induction or Tolerization of T Cells”. NeoStem has been developing its dendritic cell/tumour cell (TC/DC) technology since earlier this year when it acquired California Stem Cell. The company will launch a Phase 3 study in metastatic melanoma later this year, a development program that will be supported by the $20 million debt facility it recently secured from Oxford Finance LLC.
Asterias Biotherapeutics (ASTY), which recently received FDA clearance for a Phase I/II clinical study investigating oligodendrocyte progenitors in patients with spinal cord injury, is partnering with Cancer Research UK and Cancer Research Technology, a commercialization arm of the charity, to investigate an immunotherapy vaccine (AST-VAC2) for lung cancer. The vaccine is allogeneic (non-patient-specific) and is designed to target telomerase, a protein that is up-regulated broadly in cancer cells and functions to maintain telomere length following cell division. Asterias previously demonstrated initial safety and feasibility of a patient-specific dendritic cell-based vaccine (AST-VAC1) in patients with prostate cancer and acute myeloid leukemia (AML). However, the second iteration of this vaccine, AST-VAC2, while also being dendritic cell-based, will be derived from human embryonic stem cells. This approach is unique in the space.
ImmunoCellular Therapeutics (IMUC) is expanding its cancer immunotherapy platform with a recent licensing deal with the California Institute of Technology (Caltech). The licensed IP involves using a patient’s own hematopoietic stem cells to generate antigen-specific T cells. The company plans to address some of the limitations that have been observed with the CAR-T/T cell receptor (TCR) approaches in terms of length of immune response. Scientists that developed the technology believe that placing T cell receptors inside stem cells, rather than T cells, may prolong the response. IMUC is also developing autologous dendritic cell-based technologies targeted to various cancers. The company recently completed a Phase 2 study in glioblastoma, an indication that is also being pursued with cell-based immunotherapies by Northwest Biotherapeutics, which recently provided an update on its Phase 3 study.
As more companies enter the race to develop cell-based cancer immunotherapies, various strategies are becoming delineated. The majority of companies are taking a patient-specific approach, acknowledging that heterogeneity between patients will likely need to be addressed in order to provide long-term or curative outcomes. Asterias has separated itself from the pack by utilizing human embryonic stem cells as a source. While an allogeneic approach will provide large and reproducible quantities of vaccine at lower cost than the patient-specific approach, whether or not it will tackle heterogeneity is a question that remains to be answered. On the other side of the coin, patient-specific approaches will have to deal with additional costs around manufacturing therapies and moving them by plane between manufacturing centres and administration sites.
The major verticals in clinical development currently are dendritic cell-based vaccines and T cell-based vaccines. Dendritic cell immunotherapies consist of dendritic cells primed against specific cancer cell types. This is achieved either by mixing dendritic cells with cancer-specific proteins, or by mixing them with actual cancer cells removed from the patient prior to infusion. On the T cell side, CAR-T cells and TCRs are emerging as the two dominant approaches. However, novel methods, like ImmunoCellular Therapeutics’ HSC approach, are also getting in the mix, making for a colourful landscape.