The latest public offering follows an IPO in July 2013 which raised $27m, and a secondary round of funding last year which raised an additional $12m and - according to the Durham, North Carolina-based biotech’s SEC filing - the funds will be used to advance its pipeline of genetically modified T Cell-based therapies.
The candidates have been developed using Heat’s proprietary technology platforms, ImPACT (Immune Pan-Antigen Cytotoxic Therapy) and ComPACT (Combination Pan-Antigen Cytotoxic Therapy), both of which activate and stimulate CD8+ T cells - or ‘killer’ T cells – potentially enhancing patients' natural immune response against certain cancers.
The platforms produce candidates from allogeneic cell lines, which the company says will allow them to be mass-produced and readily available for immediate patient use.
“Unlike autologous or ‘personalized’ therapeutic vaccine approaches that require the extraction of blood or tumour tissue from each patient and the creation of an individualized treatment, our product candidates are fully allogeneic, do not require extraction of individual patient’s material or custom manufacturing,” the firm said in its Form-S1.
“Because each patient receives the same treatment, we believe that our immunotherapy approach offers logistical, manufacturing and other cost benefits compared to one-off, patient-specific approaches.”
The funding will also be used to support a phase Ib trial evaluating the firm’s non-small cell lung cancer candidate HS-110 in combination with Bristol-Myers Squibb’s PD-1 checkpoint inhibitor Opdivo (nivolumab).
Impact of ImPACTand ComPACT?
There are a number of allogeneic CAR (chimeric antigen receptor) T Cell therapy developers using their own production platforms – for example, Cellectis, Juno and Kite – but Heat says its platforms offer a number of advantages on the competition.
ImPACT functions as both an immune activator and an antigen-delivery vehicle, the company says, and “is the only adjuvant currently in clinical development that is specific to CD8+ cytotoxic T cell immune responses,” which Heat believes is especially important for developing therapeutics in oncology.
A ComPACT therapy, meanwhile, combines a pan-antigen T cell priming vaccine and T cell co-stimulator into a single product and “represents the first dual-acting immunotherapy that provides more effective stimulation of CD8+T cells and higher rates of tumour rejection than are achieved with either individual administration of traditional vaccines.”
Both technologies also do not require additional adjuvants.
“Adjuvants typically cause irritation at the injection site. HS-110, one of our product candidates, is itself an adjuvant, so we do not have to use additional adjuvants to generate and maintain an activated immune response, thereby limiting any injection site reaction to that caused by our own therapies.”