tokens: Devastating outcomes including intellectual disability and significant developmental delays are still observed in 75 % to 80 % of pyridoxine responsive individuals with good seizure control , potentially attributable to the accumulation of toxic intermediates α - aminoadipic semialdehyde ( AASA ) and its cyclic form Î” 1 -piperideine-6 - carboxylate ( P6C ) in plasma , urine and CSF .