Congress wants to open up its wallet and improve funding for medical research and speed up development of new drugs.

Apparently it needs to start with Alzheimer's and diabetes.

Those two diseases lag beind others such as cancer and AIDS in terms of medical research and breakthrough treatments, according to a new report from the Food and Drug Administration.

The report comes as lawmakers seek to make new investments into medical research. Both House and Senate appropriators have approved funding boosts of more than $1 billion over current levels for the National Institutes of Health in their fiscal 2016 spending bills.

The House also approved the 21st Century Cures Act last week, which boosts funding for NIH by $10 billion over five years and the FDA by $550 million. It also creates incentives and methods for hastening the development of new drugs. The bill now goes to the Senate.

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The report lays out the hurdles to creating new cures and treatments for diabetes, Alzheimer's and rare diseases that affect up to 200,000 people.

One of the FDA's success stories over the past decade has been cancer. Decades of research into the disease have helped drug makers predict which drugs will work and which ones will not.

Drug companies have been able to use biomarkers, which are parts of tissue that can indicate the presence of a disease. Such biomarkers can help provide insight into a patient's genetic response to a particular drug.

By knowing more about how a drug will react to a patient, drug companies have been able to avoid costly mistakes during clinical trials and get the therapies to patients much faster, the FDA said.

But there aren't any biomarkers for Alzheimer's disease, a fatal form of dementia, the agency's report said.

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"As a result, we have witnessed a series of failed attempts to find biomarkers or surrogate endpoints that can predict disease progression or drug activity," the agency added.

As with other neurological diseases, scientists don't have a basic understanding of what causes Alzheimer's. "The progression of the disease varies significantly from patient to patient for reasons that remain a mystery," according to the report.

Without available biomarkers, drug companies have made costly mistakes.

For instance, researchers thought a buildup of proteins called amyloids played a key role in Alzheimer's. That led to the development of drugs that targeted such buildups, but when tested on Alzheimer's patients they failed to show any benefit, the report said.

Only rare types of Alzheimer's have biomarkers, but the FDA said basic research into the disease's causes is needed to create more.

Diabetes is in a different camp.

There is more research on the insulin disorder, but the exact causes for both type 1 and type 2 are still unknown.

"Without this information, it is not yet possible to develop drugs targeted to prevent or treat diabetes in particular patients," the FDA said.

Diabetes has had some new treatments, though, including an inhaled insulin product approved last year. The agency has approved seven new diabetes drugs over the past two years, the report noted.

Most rare diseases have not had that kind of success. The agency has taken steps to improve the number of treatments, mainly through the orphan drug program that gives drug makers a longer monopoly on a treatment than normal if the drug treats a rare disease.

Orphan drugs now account for about a third of all novel drug and biologic approvals. But more research and collaboration into the exact causes of rare diseases is needed, the agency said.

For all of these types of diseases in the report — diabetes, Alzheimer's and rare diseases — the agency pointed to surrogate endpoints as a way to speed up clinical trials.

A surrogate endpoint is basically a shortcut to proving a drug is effective instead of longer clinical endpoints, the FDA has said. For example, a surrogate endpoint for a heart disease drug would be a patient's lower cholesterol rate, while the clinical endpoint would be waiting to find out if the person has a heart attack.

The 21st Century Cures Act would create a pathway that lets the agency approve new antibiotics based on surrogate endpoints. The goal is to hastily approve new antibiotics to treat antimicrobial resistance, a growing public health concern.

But public advocates criticized the use of surrogate endpoints.

"Data from non-clinical trials or early, small-scale clinical trials can offer misleading evidence of efficacy or miss important safety risks," according to the advocacy group Public Citizen.