Eli Lilly & Co.’s solanezumab and Roche Holding AG’s gantenerumab were selected for a long-term Alzheimer’s trial run by Washington University at St. Louis scientists seeking to block the disease’s symptoms.

The experimental medicines will be tested in a trial called DIAN TU involving 160 people with a mutation that guarantees they will develop Alzheimer’s at an early age, perhaps as young as 30, the university said in a statement Wednesday.

If the trial is successful, it may lead to those drugs being widely used for people who may have a family history of the disease. Solanezumab slowed the decline in some patients with mild Alzheimer’s and provided no benefit to more advanced patients, Indianapolis-based Lilly announced in August. On Oct. 8, an independent group of scientists confirmed the findings.

“Trying to prevent Alzheimer’s symptoms from ever occurring is a new strategy,” said John C. Morris, the trial’s principal investigator, in Wednesday’s statement. That will be the goal of the research, he said.

Lilly and Roche, based in Basel, Switzerland, have agreed to make their treatments available for the study at no cost, and will support the trial with grants. Another $4.2 million has been given to the investigation from the Alzheimer’s Association, an advocacy group based in Chicago.

The trial will be conducted by Washington University’s unit of the Dominantly Inherited Alzheimer’s Network, or DIAN, an international group of scientists studying rare genetic mutations that cause the disease. The information gathered in these patients may enable better treatment for all dementia patients.

Roche’s gantenerumab binds to clumps of beta amyloid, a protein thought to cause the disease. The drug is thought to help remove the clumps from the brain, and is in a mid- to late-stage company trial that started in 2010. Lilly's solanezumab removes the beta amyloid before it forms plaques.

Another Lilly drug, called a beta secretase inhibitor, is in testing by the company and may be included in the university research as well, according to Wednesday’s statement. That drug is thought to work by reducing the amount of beta amyloid produced in the brain.

The trial, which may start early next year, will test the medicines in inherited early-onset Alzheimer’s patients. The researchers will see if the treatments can prevent the loss of brain function.