Development of PTI DX a blood based diagnostic for Alzheimer s disease

Abstract PTI is developing PTI DX a novel quantitative blood based diagnostic candidate for Alzheimerandapos s disease AD A non invasive and inexpensive AD diagnostic is sorely needed particularly one with the ability to detect early pathological changes that precede cognitive symptoms PTI DX measures the ratio of two protein fragments in plasma and is a companion diagnostic biomarker for our therapeutic candidate PTI PTI disrupts and prevents filamin A FLNA andapos s association with the nicotinic acetylcholine receptor nAChR which amyloid beta A hijacks to hyperphosphorylate tau protein We have tested over plasma samples and show two orders of magnitude significant differences between patients with AD diagnoses confirmed by imaging or CSF markers and age matched normal controls These two groups are distinguished with accuracy In one of two blinded studies PTI DX distinguished MCI with confirmed AD pathology MCI AD from MCI with suspected non amyloid pathology MCI SNAP with accuracy in the other this distinction needs confirmation by imaging In this proposal we will compare additional MCI AD and MCI SNAP samples and determine disease specificity of the assay by testing archived plasma samples from patients with dementia with Lewy bodies Frontotemporal Dementia and Parkinsonandapos s disease alongside AD MCI AD MCI SNAP early onset familial AD FAD cancer and elderly or young controls As PTI DX is currently in Western blot format we will develop an ELISA assay and compare it to an automated Western blot format using ProteinSimpleandapos s WesTM In Phase II we will generate proprietary antibodies by immunizing with carefully selected peptides and recombinant proteins these polyclonal antibodies will be screened and tested to determine optimal combinations The corresponding immunogens will then be used to develop monoclonal antibodies The sandwich ELISA we envision will capture all fragments of interest and separately detect two specific protein fragments With final monoclonal antibodies and a final ELISA or Wes format selected we will perform a new blinded study of up to de identified plasma samples from the AIBL study At the conclusion of this work PTI DX will be ready for commercialization or partnering Project Narrative Pain Therapeutics Inc PTI is developing PTI DX a novel quantitative blood based diagnostic test for Alzheimerandapos s disease In two separate blinded studies of over samples PTI DX differentiated AD from elderly normal control subjects with accuracy and mild cognitive impairment due to AD MCI AD from MCI suspected non amyloid pathology MCI SNAP with accuracy In the current proposal we will first determine specificity of the assay for AD or MCI due to AD versus other dementias In Phase II we will synthesize or clone peptides and protein fragments to use as immunogens to generate proprietary polyclonal and then monoclonal antibodies We will convert the existing Western blot assay to ELISA or automated Western blot and with final format and monoclonal antibodies perform a new blinded study of clinical trial plasma samples