Table 2. Ongoing and planned clinical trials of cell therapies for the treatment of PD. TBD, to be determined.

Trial	Transeuro182 NCT01898390	ISCO183 NCT02452723	CiRA125	Chinese Academy of Sciences184 NCT03119636	American multicentre case report185	Summit for PD (in set up)59	NYSTEM-PD186 (in set up)	European STEM-PD187(in set up)
Cell source	Foetal ventral mesencephalona	Parthenogenetic neural stem cellsb	Allogenic iPSCsc	Parthenogenetic embryonic stem cell derived neural precursorsd	Autologous iPSCse	Autologous iPSCsf	H9 embryonic stem cellsg	RC17 embryonic stem cellsh
Cryopreservation of the cell product	No	Yes	No	Data not available	Yes	Yes	Yes	Yes
Screening of cell product for genetic variance/quality control	None	Yes, flow cytometry and RT- PCR to assess markers of pluripotency.	Yes, sequencing for genes of interest	Data not available	Whole genome sequencing	Whole genome sequencing	Yes, Karyotype analysis by G- banding. Viral testing. Genetic testing TBD.	Yes, flow cytometry and RT- PCR to assess markers of pluripotency and midbrain dopaminergic progenitors. Genetic testing TBD
Functional testing	Structural and functional MRI 18F-Dopa PET 11C-PE2I PET 11C-DASB PET	MRI 18F-DOPA PET	MRI 18F-FLT-PET	MRI DAT-SPECT	18F-DOPA PET MRI CT scan	18F-DOPA PET DAT- SPECT 18F-FLT PET	18F-DOPA PET 11C-PE2I PET MRI	MRI 18F-DOPA PET 11C-PE2I PET
Immunosuppression	Cyclosporine, Azathioprine and Prednisolone	Yes, but unclear	Tacrolimus	Data not available	None	None	Tacrolimus, mycophenalate, basiliximab, prednisolone.	TBD
MHC Matching?	No	No	Yes	Two groups - one HLA matched one mismatched	Autologous transplant	N/A	No	No
Patient cohort	30-68y/o early- stage PD patients	30-70y/o moderate to severe PD patients	50-70y/o moderate PD patients	50-80 y/o moderate PD patients	One 69 y/o PD patient	45-70 y/o moderate PD patients.	40-70y/o moderate PD patients.	Moderate stage PD patients 40- 70y/o
Date of first-in-human transplant	2015	2016	2018	2017	2018	TBD	TBD	TBD

^aGrafting of foetal ventral mesencephalic tissue has previously demonstrated efficacy in PD animal models and patients^27,55,57,188. ^bNSCs grafted into the brains of rodents and non-human primates was safe but with minimal clinical efficacy^65,67,68.

^cClinical grade iPSC-derived dopaminergic progenitors have demonstrated safety and efficacy in rodent and non-human primate PD models⁶².

^dClinical grade ESC-derived neural precursors significantly improved motor dysfunction in some MPTP lesioned non-human primates, in the absence of tumour formation for up to 2 years¹⁸⁴.

^ePD patient-derived iPSC-derived dopaminergic precursors significantly reversed motor deficits in 6OHDA lesioned rats, without tumour formation¹⁸⁵. Results were corroborated in one PD patient, who demonstrated clinical benefit up to 2 years after grafting, without the onset of serious adverse events¹⁸⁵.

^fData pertaining to the safety and efficacy of autologous iPSC-derived dopaminergic neurons is underway. 10 patient-derived iPSC lines have been successfully generated⁶⁴.

^gClinical grade H9 ESC-derived dopaminergic progenitors have demonstrated safety and efficacy in preclinical PD models^135,150.

^hClinical grade ESC-derived dopaminergic progenitors have demonstrated safety and efficacy in preclinical PD models^84,88.