Eli Lilly has stopped a Phase II study for an investigational Alzheimer's disease treatment due to potential liver problems.

LY2886721, a beta secretase (BACE) inhibitor is being investigated as a once-daily treatment for its potential to slow the progression of Alzheimer's disease. However, the trial is being terminated due to abnormal liver biochemical tests identified as part of routine monitoring.

Jan Lundberg, science and technology head of Lilly Research Laboratories, said that "while stopping this Phase II study for our BACE inhibitor is disappointing, patient safety is of utmost importance". He added that "discovering and developing medicines for devastating diseases like Alzheimer's is fraught with many challenges", but he insisted that the firm is still committed to the area.

Furthermore, Lilly said it believes the abnormal tests observed in the study "are not related to the BACE mechanism and continues to be interested" in developing these inhibitors. It will further evaluate this data prior to determining next steps for the entire LY2886721 clinical development programme.

The company expects to incur a charge associated with the decision to stop this trial but it is not expected to be material.

On a brighter note, Lilly and partner Incyte Corp have presented more promising data on their investigational JAK inhibitor baricitinib for rheumatoid arthritis.

The companies announced 52-week data from a Phase IIb study of baricitinib at the European Congress of Rheumatology meeting in Madrid which showed that clinical improvements previously observed at week 24 were sustained for the full year in RA patients. Specifically, 49% of patients were ACR50 responders (ie a 50% improvement in their condition) after 52 weeks compared to 41% at week 24. For the full year, 21% reached ACR70 compared with 27% after 24 weeks.

To date, baricitinib, an orally administered selective JAK1 and JAK2 inhibitor,  has demonstrated "an acceptable safety profile and side effects have generally been straightforward to manage", said Oxford University's Peter Taylor. He added that "these encouraging findings support further investigation of this new drug in RA".

Baricitinib is already in Phase III for RA and in Phase II for psoriasis and diabetic nephropathy.