Gotham City Research published Part II of its investigation into Sumitomo Chemical and Sumitomo Pharmaceutical, focusing on the Center for iPS Cell Research & Application (CiRA) and its founder Dr. Shinya Yamanaka. Sumitomo Pharma targets 350 billion JPY in iPS cell revenue, including from Amchepry, and CiRA is its research partner, iPS cells supplier, and trial conductor. Gotham City Research identified two well-documented cases of fraud involving CiRA and Yamanaka (2014 and 2018), plus 8 additional problematic cases — including one research paper where the Amchepry trial's lead investigator is an author. Amchepry depends entirely on CiRA's integrity, which Gotham City considers suspect and unreliable. Notably, Takeda recently terminated its 10-year partnership with CiRA while Sumitomo goes all-in. Gotham City's opinion is that Sumi Pharma's FY2025 financial statements are misstated by 116-165 billion JPY and will be restated, with an investigation to follow.
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The Core Allegation
Gotham City Research's Part II report on Sumitomo Chemical and Sumitomo Pharmaceutical focuses on the Center for iPS Cell Research & Application (CiRA) and its founder Dr. Shinya Yamanaka.
Gotham City Research's opinion: Sumi Pharma's FY2025 financial statements are misstated by 116-165 billion JPY. Financial statements will be restated and the Company will face an investigation.
The CiRA Dependency
- Sumitomo Pharma targets 350 billion JPY in iPS cell revenue, including from Amchepry
- CiRA is SP's research partner
- CiRA is the iPS cells supplier for the Amchepry trials
- CiRA conducts the trials and research
- CiRA is paid by Sumitomo Pharma, with a relationship since 2011
Amchepry's entire revenue thesis depends on the integrity of CiRA.
Prior Fraud Cases at CiRA
There are two well-documented cases of fraud involving CiRA and its founder Shinya Yamanaka:
- 2014
- 2018
8 Additional Problematic Cases
Gotham City Research has discovered 8 additional problematic cases, including:
- 1 research paper where the Amchepry trial's lead investigator is an author
This suggests a pattern of research integrity issues at CiRA, not isolated incidents.
Amchepry Depends on a Suspect Partner
Amchepry depends on the integrity of CiRA, but CiRA is suspect, unreliable.
The entire commercial thesis for Sumitomo Pharma's iPS cell revenue rests on the credibility of an institution with documented fraud cases.
Takeda's Exit vs. Sumitomo's All-In Bet
Sumitomo Pharma is going all-in on CiRA while Takeda recently terminated its 10-year partnership with CiRA.
Takeda's exit from a decade-long relationship is a significant red flag that Sumitomo is ignoring.
The Financial Misstatement
Gotham City Research's opinion:
- FY2025 financial statements are misstated by 116-165 billion JPY
- Financial statements will be restated
- The Company will face an investigation
subsequent events
- 2011Sumitomo Pharma begins paid relationship with CiRA
“CiRA is paid by Sumitomo Pharma, with a relationship since 2011”
- 2014First documented fraud case involving CiRA and founder Shinya Yamanaka
“Two well documented cases of fraud involving CiRa and its founder Shinya Yamanaka, in 2014 and 2018”
- 2018Second documented fraud case involving CiRA and founder Shinya Yamanaka
“Two well documented cases of fraud involving CiRa and its founder Shinya Yamanaka, in 2014 and 2018”
- Pre-2025Takeda terminates its 10-year partnership with CiRA
“Sumitomo Pharma is going all-in on CiRA while Takeda recently terminated its 10 year partnership with CiRA”
- 2025Gotham City Research publishes Part II report identifying 8 additional problematic cases
“We have discovered 8 additional problematic cases, including 1 research paper where the Amchepry trial's lead investigator is an author”
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