QST PET aSyn — process / contract / freedom to operate / GLP-Tox 20230808 plan, 20230714 Biomarker FlytoAs, Postmortem aSyn opener

GLP-Tox

	content
cost	approx. 8 mil yen + GLP test substance manufacturing cost
20230706	Keep discussion with QST and Ono about SPAL-T-06 GLP tox study and longitudinal study
from QST	Higuchi from QST: Join both discussion for US & Jap to have identical protocols as much as possible.
GLP tox report	in Japanese will be reported in summer 2024
	than the English version will be generated by March 2025
20230808
1. Final report	in English will be obtained in Sept 2024.
2. Outline	Extended Intravenous Single Dose Toxicity Study of SPAL-T-06 in Rats
Toxicity evaluation group	male and female, N=10, after single intravenous administration, autopsy the next day
Recovery group	male and female, N=5, autopsy 14 days after single dose
Dose	0.5, 50 μg/kg
Rationale for setting the dose	The maximum clinical dose of [18F]SPAL-T-06 is assumed to be 5 mCi/person. When administered to a human with a maximum body weight of 40 Kg, the clinical maximum dose is 0.0481 μg/kg. Low dose set as 5 μg/kg to ensure a margin of safety 100 times. Based on the ICH M3 guidelines, the maximum dose is set as 50 μg/kg, which is 1000 times the maximum human dose.
Evaluation items	general condition, body weight and food intake, hematology and blood biochemistry tests, organ weight, autopsy, histopathological examination

Higuchi from QST recommended Kd value of 2.5 nM.

(20230714) 3. Biomarker FlytoAs

(part of the initial evaluation of [18F]SPAL-T-06 in vivo PET studies performed in WT rat)

• 90 min dynamic PET scan
• WT rats devoid of any aggregate proteinopathies so no specific binding anticipated. Looking only at brain penetrability along with wash in and out kinetics.
• [18F]SPAL-T-06 behaved as expected with good brain penetrability and rapid washout.
• Homogenous brain uptake observed.

(SPAL-T-06 vs C05-05 seems to be somewhat more potent (QST, Higuchi). 20230708 planned selectivity study from Takeda.)

Postmortem aSyn

a-syn mRNA levels (quantitative real time PCR), did not differ significantly between groups in any brain regions examined; levels of soluble α-syn proteins (ELISA) were significantly lower in 4 of the 5 regions for DLB patients, and in 2 of the 5 regions for patients with PD vs controls (frontal cortex; α-syn monomer; T-aSyn oligomer (cf 4) DLB-MSA; Soluble (oligomers); Insoluble).

Comparison oligomers (% area) for the proposed Lewy body staging system, after substitution by presence or absence of dementia ratification. Figure shows are weights of selected fields and dispersion ratio (rated)…

In PD (and in DLB) all regions are frequently affected (70-80%), but not BG II 8 (1) but Pa 30% Pe 38% H 47% N 10% (16: 0/5= 16: 비슷처럼 brainstem이 or 16: 도 다? brainstem만 100% (경기도 일정)) (Js: 이거 cortex처럼! 일거 같음 (실제로 작 일정))

Classification rules for the proposed implied stages typing in Lewy body disorders. Disease (cases are derived from the Third Dementia with Lewy Bodies Consortium criteria 4. Cases are derived from the Third Dementia with Lewy Bodies Consortium criteria 4. Notes: regions in italics highlight the dependent on the case rating. Score on which the case rating is based. Some implied stages may be classified as ambiguous if no decisive features can be considered (Pa eg, examined when this issue arises. We are aware of additional staging schemes that may be useful for example a frequent in olfactory bulb is associated with brainstem disease and have shown a deeper PD-related α-synuclein dendrosome). However, the absence of staging in the olfactory bulb is associated with brainstem disease only it doesn’t fit on the staging scheme implied by frequency, however, it always with a positive substantial nigra. As staging schemes implied by frequency, however, it always with a positive substantial nigra.

Implied stage from DLB/SS data
Olfactory Bulb (OB) Brainstem (Pen, Pa)
Limbic Limbic-Temporal
Neocortical-Frontal

Uncertain Spans

location	transcription	uncertainty
Implied stage table	column-to-cell alignment for Olfactory Bulb (OB) Brainstem (Pen, Pa) / Limbic Limbic-Temporal / Neocortical-Frontal	reads as written; preserved verbatim.