Landmark 175 · Trial in people
Spheramine (STEPS)
In 71 people, the implants did no better than a fake operation. Movement scores changed by about the same amount in both groups.
In short
Retinal pigment cells stuck to tiny gelatin beads and placed in the putamen did not improve movement more than a fake operation in 71 people with advanced Parkinson's.
- What it is
- Trial in people
- Outcome
- Did not work
- When
- 2008–2011
- Size
- 71 people · Phase 2
- Approach
- Replace or repair what's lost
- Research lane
- Cell replacement
- Trial registry
- NCT00206687
- Last checked
- 19 Oct 2026
The research record
This is the project's file for this landmark, as written and checked. Sources are listed at the end; anything not yet confirmed is marked "Not yet verified".
Who
Titan Pharmaceuticals and Bayer Schering (Bayer funded the trial). Topline result 2 July 2008; full paper by Gross et al. in The Lancet Neurology 2011;10:509–519. Registered as NCT00206687; the trial started in January 2003.
What happened
After the fetal-graft trials (landmark 3), a more practical cell source was sought. Human retinal pigment epithelial (RPE) cells make levodopa. Spheramine put about 325,000 of them per side, on gelatin microcarriers, into the putamen (a movement-control area).
- Design. Phase 2b, double-blind, sham-surgery-controlled (patients in the control arm got partial burr holes only). 71 people aged 36–70, symptomatic for at least 5 years, Hoehn and Yahr stage 3–4, with OFF motor scores of 38–70. 35 transplanted, 36 sham.
- Result. Change in the OFF-medication motor score at 12 months: -10.5 points with cells versus -10.1 with sham (p=0.9). Overall adverse events were similar, but more surgery- or cell-related events occurred in the transplant group. Deaths: 2 sham, 7 transplant (one possibly related).
- Aftermath. Titan's release on 2 July 2008 said Spheramine missed its primary and key secondary endpoints; a Bayer spokesman said it would not develop the drug further. Titan's later filings say Bayer Schering gave notice of termination of the licence in September 2008.
Why it moved us toward a cure
Together with the fetal-graft trials, it showed that replacing dopamine production at the putamen with a levodopa-making cell, and not true dopamine neurons, was not enough. It set the standard of sham controls and pushed the field toward stem-cell-derived dopamine neurons (landmark 10).
Outcome
Dead end for RPE-cell implants. It is a symptom-and-replacement trial rather than a slowing trial, listed here because it closes a cell-replacement route.
Sources
- Gross et al., Lancet Neurol 2011, DOI 10.1016/S1474-4422(11)70097-7 (PMID 21565557)
- ClinicalTrials.gov NCT00206687 · Titan/Bayer topline, 2008
- Titan release, 2 Jul 2008 · PharmaTimes on Bayer's exit
- Not yet verified: the reasons the authors give for failure (e.g. cell survival); the Bayer quote (read in a search summary of PharmaTimes, not the page); the September 2008 notice (Titan's 2010 filing, read in a search summary).
How it connects
Built on
- builds on First fetal dopamine-cell transplants · 1987
Led to
None recorded.