Contributions
Abstract: EP1506
Type: ePoster
Abstract Category: Therapy - disease modifying - Neurorepair
Background: Inducing remyelination is a desired therapy strategy for patients with multiple sclerosis. For clinical trials, outcome measures to detect remyelination are needed, and the P100 latency of visual-evoked responses (VEPs) is a suitable surrogate for remyelination of the optic nerve. We have previously shown that the test-retest variability of VEP P100 can be reduced by independent verification (Thomae et al., 2010).
Methods: We investigated the effect of P100 verification for longitudinal VEPs that were recorded within our phase I/II clinical trial with recombinant human growth hormone for remyelination in patients with multiple sclerosis. VEPs of all 24 patients were recorded by standard operating procedures. Verification of cursor positioning was carried out by a physician blinded for the sequence of recordings for each patient"s eye.
Results: 279 VEPs were processed. In 9 recordings (3%), the cursor for P100 had to be corrected, resulting in P100 latency increase by a median of 8.25 ms (range 0.9-57ms); once, latency changed from non-reproducible to a measurable value. The underestimated P100 would have implied remyelination by mistake. Taking into account that these VEPs were recorded in a single centre clinical trial, this observation probably underestimates reproducibility problems in multi-centre studies.
Conclusion: Centralized VEP verification appears necessary for multi-center remyelination trials employing VEP latencies as surrogate outcome.
Disclosure: The clinical trial was funded by the German Ministry of Education and Research (BMBF) through the Translational Centre for Regenerative Medicine; a drug donation was provided by Pfizer GmbH. The authors had no conflicts of interest related to this project.
Abstract: EP1506
Type: ePoster
Abstract Category: Therapy - disease modifying - Neurorepair
Background: Inducing remyelination is a desired therapy strategy for patients with multiple sclerosis. For clinical trials, outcome measures to detect remyelination are needed, and the P100 latency of visual-evoked responses (VEPs) is a suitable surrogate for remyelination of the optic nerve. We have previously shown that the test-retest variability of VEP P100 can be reduced by independent verification (Thomae et al., 2010).
Methods: We investigated the effect of P100 verification for longitudinal VEPs that were recorded within our phase I/II clinical trial with recombinant human growth hormone for remyelination in patients with multiple sclerosis. VEPs of all 24 patients were recorded by standard operating procedures. Verification of cursor positioning was carried out by a physician blinded for the sequence of recordings for each patient"s eye.
Results: 279 VEPs were processed. In 9 recordings (3%), the cursor for P100 had to be corrected, resulting in P100 latency increase by a median of 8.25 ms (range 0.9-57ms); once, latency changed from non-reproducible to a measurable value. The underestimated P100 would have implied remyelination by mistake. Taking into account that these VEPs were recorded in a single centre clinical trial, this observation probably underestimates reproducibility problems in multi-centre studies.
Conclusion: Centralized VEP verification appears necessary for multi-center remyelination trials employing VEP latencies as surrogate outcome.
Disclosure: The clinical trial was funded by the German Ministry of Education and Research (BMBF) through the Translational Centre for Regenerative Medicine; a drug donation was provided by Pfizer GmbH. The authors had no conflicts of interest related to this project.