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Promise Seen in Drug for Retardation Syndrome

Bryce

Vickmark for The New York Times

After learning that their son,

Andy, had fragile X syndrome, Clapp and her husband, Dr.

Tranfaglia, started the Fraxa Research Foundation to fund research for the

condition.

By GARDINER HARRIS

Published: April 29, 2010

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An

experimental drug succeeded in a small clinical trial in bringing about what

the researchers called substantial improvements in the behaviors associated

with retardation and autism in people with fragile X syndrome, the most common inherited

cause of these mental disabilities.

Enlarge This Image

Bryce

Vickmark for The New York Times

Clapp and her son, Andy

Tranfaglia, who was born with fragile X syndrome. She works to raise funds for

research.

The

surprising results, disclosed in an interview this week by Novartis,

the Swiss pharmaceutical giant that makes the drug, grew out of three decades

of painstaking genetic research, leaps in the understanding of how the brain

works, the advocacy of families who refused to give up, and a chance meeting

between two scientists who mistakenly showed up at the same conference.

“Just

three years ago, I would have said that mental retardation is a disability needing

rehab, not a disorder needing medication,†said Dr. R. Insel,

director of the National Institute of Mental Health, who was

told of the Novartis

trial results. “Any positive results from clinical trials will be

amazingly hopeful.â€

Dr. Mark C.

Fishman, president of the Novartis Institutes for BioMedical Research,

cautioned against too much optimism. The trial involved only a few dozen

patients, only some of whom benefited from treatment. The drug is likely to be

years away from being commercially available and could fail in further clinical

trials, he said.

“We

have been reluctant to make this public because we still need to do more

experiments, do them correctly and in a bigger way,†Dr. Fishman said.

“But our group feels pretty good about the data.â€

If

authenticated in further, larger trials, the results could also become a

landmark in the field of autism research, since scientists speculated that the

drug may help some patients with autism not caused by fragile X, perhaps

becoming the first medicine to address autism’s core symptoms.

One child in

five thousand is born with fragile X syndrome, with mental effects ranging from

mild learning disabilities to retardation so profound that sufferers do not

speak, and physical effects that include elongated faces, prominent jaws, big

ears, and enlarged testes. It mostly affects boys and earned its name because,

under a microscope, one arm of the X chromosome seems nearly broken, with part

hanging by a thread.

The gene for

fragile X was discovered in 1991. Work since then has found that fragile X

patients seem to experience an overload of unchecked synaptic noise —

synapses being the junctions between brain neurons. The Novartis drug and

others like it are intended to lower the volume of this noise so memory formation

and high-level thinking can take place, allowing children to develop normally.

The Novartis

trial, which began in 2008 in Europe with data analysis completed this year,

was too brief to observe effects on basic intelligence. Instead, researchers measured

a range of aberrant behaviors like hyperactivity, repetitive motions, social

withdrawal and inappropriate speech. They gave one set of patients the drug and

another a placebo, and after a few weeks switched treatments, with both doctors

and patients unaware of which pill was which.

The results

of the trial were something of a jumble until Novartis scientists noticed that

patients who had a particular, undisclosed biological trait improved far more

than others. “The bottom line is that we showed clear improvements in

behavior,†Dr. Fishman said.

Told of the

results, two parents of a fragile X patient were euphoric.

“This

is what we have been working for and hoping for since our son was diagnosed

with fragile X 17 years ago,†said Clapp, president and co-founder

of the Fraxa Research

Foundation, a nonprofit organization dedicated to financing fragile

X research. “This may be the key to solving the mystery of autism and

other developmental disorders.â€

Geraldine

Dawson, chief science officer at Autism Speaks, the world’s largest

autism advocacy organization, said that a growing body of research suggests

that the many genetic causes of autism all seem to affect synapses, suggesting

that a treatment for one form of the disease might help others.

“The

exciting thing about these results is that it is our hope that these same

medications may have similar positive benefits for people with autism who

don’t have fragile X syndrome,†Dr. Dawson said.

Between 10

percent and 15 percent of autism cases result from fragile X syndrome or some

other known genetic defect. While fragile X is the most common inherited cause

of mental retardation, Down syndrome — which also causes

retardation — is more common but is not inherited.

The Novartis

trial results were not published or peer reviewed, and for commercial reasons

Dr. Fishman refused to divulge many details. Dr. Luca Santarelli, head of

neuroscience at Roche,

confirmed that Roche is in the midst of testing a similar medicine in fragile X

patients at four sites in the United States.

“So

far we like what we see,†Dr. Santarelli said in his only

characterization of their study.

One reason

for the euphoria surrounding the Novartis trial is that it was seen as an

especially difficult test of the drug’s effects. For ethical reasons,

Novartis tested the drug only in adults. But the company and outside

researchers believe that such compounds may prove most effective in young

children, whose brains are far more likely to respond rapidly when barriers to

learning are removed.

“This

is perhaps the most promising therapeutic discovery ever for a gene-based

behavioral disease,†said Dr. M. Scolnick, former research chief

at Merck and now director of the Stanley

Center for Psychiatric Research at the Broad Institute at Harvard

and the Massachusetts Institute of Technology.

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Promise Seen in Drug for Retardation Syndrome

Published: April 29, 2010

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(Page 2 of

2)

Dr. Scolnick

has not seen the results of the Novartis trial, but was told of them and

concluded that if the drugs work in fragile X, “there’s nothing to

say that they won’t work in some cases of broader autism-spectrum

disorders.â€

T. Warren/Emory University School of Medicine

The arrow indicates a fragile X

chromosome.

An Unlikely

Beginning

The roots

for the Novartis results began in 1982 when T. Warren, then a graduate

student in genetics at Michigan

State University, was looking for a job and something to research. A

friend told him about fragile X and, with the same reflection he might use to

pick a novel for a long flight, he decided that he wanted to find the gene that

caused it.

“I had

no idea how hard this would be,†Dr. Warren said. Nine years later, Dr.

Warren, then at Emory

University, was part of an international team that won a fierce

competition by isolating the gene. The discovery was front-page news around the

world, and experts predicted that widespread fetal testing and therapies were

in the offing.

The

predictions were premature because, like most of genetic research, discovering

how the flawed gene caused disease was far harder than anticipated and required

multiple leaps in neurology and biology. And even with those, much remains

mysterious.

Fragile X is

caused by a genetic stutter in which a portion of the gene gets repeated like a

scratched album. With each subsequent generation, the number of repeats tends

to rise. So if a mother has 10 repeats, her child might have 11 or 12. For

reasons that are not well understood, however, this process of repeat

amplification can suddenly go haywire. So mothers who have 55 or more repeats

tend to have children with hundreds.

In anyone

with 200 or more repeats, the body shuts off the gene. Since genes are used to

make proteins, this genetic silencing means the encoded protein is never made.

The absence of this protein in cells causes the wide-ranging effects of fragile

X syndrome. Those with 55 to 200 repeats are considered carriers, and recent

research shows they can have severe neurological declines late in life that

mimic Alzheimer’s and Parkinson’s.

Many

geneticists would have moved on to other research topics after finding a

disorder’s underlying gene. But Dr. Warren met affected children and

their parents. Instead of family pictures, Dr. Warren’s desk displays a

framed photo of a fragile X chromosome.

“I

could not imagine telling someone like Clapp that we were not going to

pursue this research anymore,†he said.

So he kept

on. Years of work by him and others found that the protein missing in those

with fragile X normally seems to act as a sort of traffic cop at brain

synapses, helping to stop or slow brain signaling at crucial intervals. It does

this by sopping up the genetic instructions needed to produce proteins that

encourage brain signaling. Regulating this flow of electronic pulses across the

brain is crucial for the brain’s ability to learn and mature.

Dr. Warren

was puzzling over how to recreate that synaptic traffic cop when, because of a

scheduling conflict, he showed up in 2001 at the wrong scientific conference

and happened to sit next to Mark F. Bear, a neuroscience professor at M.I.T.

who had just given a presentation about compounds that seemed to work in

synapses to speed the creation of proteins — including the one missing in

fragile X patients.

The two got

to talking and decided to collaborate. They found that if Dr. Bear

reverse-engineered his compounds, they seemed to slow brain transmissions.

Instead of a traffic cop, the brain would get speed bumps. Not ideal, but

perhaps adequate in lowering the synaptic noise enough to encourage learning

and the moderation of the kind of synaptic traffic jams that in fragile X

children can lead to seizures.

Sure enough,

mice, fish and fruit flies that through genetic engineering were made to have

fragile X seemed to become normal when given Dr. Bear’s compound. The

Novartis compound is a member of the same drug family.

“We

have been promising for a long time that unlocking the molecular basis for

hereditary diseases would lead to dramatic therapeutic advances, and that promise

is finally coming true,†said Dr. Francis

S. , director of the National Institutes of Health, in discussing

the science leading up to the trial. “But it has not been easy.â€

A Search for

Treatment

A hundred

years ago, Clapp would have died giving birth to Andy, her child with

fragile X.

“Andy’s

head was too big to get out without a C-section, he would have killed me, and that

would have taken care of the fragile X gene,†she said.

But Ms.

Clapp and Andy did survive. And despite going to some of the best hospitals in the country, four years would

pass before Andy’s condition was properly diagnosed.

When a

doctor finally thought to do a fragile X test, Ms. Clapp and her husband, Dr.

Tranfaglia — both Harvard graduates with post-graduate degrees

— researched the disease and came to two conclusions: fragile X was

potentially treatable; and only about five researchers in the world were

working toward a cure.

“And I

thought, what if all five walk across the street at the same time and get hit

by a Mack truck?†Ms. Clapp said. “That is not going to get us

there.â€

So the two

started the Fraxa Research Foundation. Remarkably, their efforts seem to be

paying off and may finally offer hope not only to those who with fragile X but

to carriers like Andy’s sister, .

“I’ve

always known my kids have a chance of having it,†, 18, said in a

recent visit to the family’s house. “But I’m not going to

have kids for at least 10 years anyway, and they’ll have a cure for by

then.â€

She paused,

looked at her mother and said: “You’ve got 10 years.â€

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