Jason Marder watched the inevitable decline of his younger brother, who died of Alzheimer's disease at the age of 50. Then, just after his 60th birthday, he too, began to exhibit subtle, early symptoms -- forgetfulness and difficulty focusing on conversations.
At his birthday party, "I noticed he had a hard time keeping track of the presents," said he wife, Karin Marder. "He would forget small things -- like saying he went to the movies when he didn't."
The memory loss progressed, and in 2004, Marder got the dreaded diagnosis: Alzheimer's, a disease that affects 5.1 million Americans.
"It was devastating," said his wife, who works in business apparel. "I thought our lives were going to end."
But today, eight years after his diagnosis, Marder isn't any worse off. He has shown no further memory loss and has remained stable.
The Marders credit intravenous immunoglobulin, or IViG, therapy and a clinical trial that is swirling in controversy this week after an announcement of study results by the Alzheimer's Association International Conference 2012 in Vancouver.
Some doctors hailed the therapy as "exciting," something that could potentially stabilize the disease, while others said the research is inconclusive and the study -- with only 16 subjects -- was too small.
Nonetheless, today Marder, now retired from working in apparel, continues his independent lifestyle, playing tennis and biking in his native New York City.
"Things are going really nicely. I can't complain," said Marder, now 70. "I don't feel any going backwards."
"This drug saved his life," said Karin Marder. "He's independent. He gets on the subways, bikes up and down the Hudson River, gets to go out with friends. He goes to the senior center twice a week. He does creative writing."
For the past five years, Marder has been part of a clinical trial with Dr. Norman R. Relkin, director of the Memory Disorders Program at New York-Presbyterian/Weill Cornell Medical Center.
Relkin presented data that found,overall, that 11 study participants who received the immunotherapy Gammagard (IViG) for three full years showed improvements in cognition, memory, daily functioning and mood.
"We are seeing encouraging results," Relkin told ABCNews.com. And despite negative publicity, "I don't want people to give up hope for symptomatic treatment of the disease".
Intravenous Immunoglobulin is a mixture that contains molecules pooled from plasma, a component of human blood. It is used to treat various autoimmune, infectious and idiopathic diseases, and its supply is therefore limited.
IViG works by using the body's natural defense or immune system and anti-amyloid antibodies. A protein called beta amyloid accumulates in the brain of those who have Alzheimer's.
"We don't know exactly what it targets, but we do know it contains all antibodies that the body produces," said Relkin. "It alters the function of the immune system and decreases inflammation in the brain".
He said that his research team found the rate of brain shrinkage had slowed and the study had "exceeded criteria" to go forward with a phase III trial.
"Typically, untreated Alzheimer's disease shows cognitive decline in three to six months," said Relkin. "Those treated with typical AD drugs show decline in six to nine months. Four out of four patients in the [phase IIB] extension trial were unchanged over a three-year period."
As for Marder, he still has some memory problems, but he can dress himself, cook, clean and walk around the neighborhood.
"I can be away from him for one to two nights," said his wife, Karin.
Every two weeks, a nurse comes to Marder's home and sets up the infusion, which takes about four hours.
"I am happy to spend the time," he said. "Then I walk out of my house and go bike riding."
Besides a minor rash that crops up three to five days after getting the drug, Marder has had no ill side effects with the treatment. "He hasn't even had a cold in five years," said Marder's wife.