Originally created 08/30/98

Technology takes pain out of shots



ATLANTA -- The cancerous tumor in his leg was painful enough for 11-year-old Matthew Loibl. A daily barrage of needle pricks just added to his misery.

"It means a lot of bruises," said Matthew of Stone Mountain, who used to get stuck as often as five times a day before a permanent catheter was implanted in his arm. "I've been poked so many times that I've developed an allergy to the Band-Aids."

Relief could be on the way for Matthew and other patients who are tired of having their arms, thighs or rear ends pricked by hypodermic needles. A pair of professors at Georgia Tech are working on "microneedles," a pain-free way to deliver drugs into the body.

The concept is relatively simple: replace one long, scary needle with a patch containing hundreds of tiny, painless ones. The microneedles are so short and thin -- about 25 could fit inside a regular hypodermic needle -- they don't reach the nerves and patients don't feel a thing.

"I was working on using electronic pulses to create openings in the skin, but that still created pain," said Mark Prausnitz, a professor of chemical engineering at Tech. "So I thought, there has to be a simpler way of getting drugs into the body, and that took me to this."

Microneedles, which could be available within four or five years, puncture the skin, but only the outer layer of dead skin.

"It is a very elegant way of avoiding pain," said Rita Vanbever, a researcher at the Massachusetts Institute of Technology who is working on finding alternative methods of drug delivery.

Reducing the pain and fear associated with needles aren't the only benefits.

"It is always a goal to avoid injection," Ms. Vanbever said. "There are many disadvantages to injection, such as an infection you can get penetrating into the skin."

The microneedles are 10 to 20 microns long -- a micron is one-thousandth of a millimeter -- and are about as thick as a single human hair.

A standard array includes about 400 microneedles and is about one-inch square. It resembles the patches used to deliver other kinds of drugs, including nicotine.

Using fabrication techniques mastered by Georgia Tech professor Mark Allen, the microneedles are infinitely sharper than a standard needle and are made out of silicon, but other substances could be used.

The project is one of many around the country exploring needle alternatives. Others include lasers and ultrasound, which can create painless holes in the skin, and the use of polymers to make it possible to inhale different kinds of drugs.

Mr. Prausnitz cautioned that there will always be a place for traditional needles -- especially when drugs need to be administered directly into the blood stream.

But for drugs that can be delivered subcutaneously, or under the skin, microneedles could give doctors greater control.

"Once a pill or a needle is inside the body, it's out of anyone's control," said Mr. Prausnitz, who envisions hooking his device up to an electronic pump. "With microneedles, you can have a lot more control over what is going on."

It could be used to deliver different kinds of chemotherapy or insulin -- good news for diabetics, some of whom need several shots a day.

The researchers hope to begin human testing soon. Mr. Prausnitz recently began discussions with drug companies, which would manufacture and market the product, and the technology might hit the market by early next century.

None too soon for Matthew and his mother Carol.

"It's upsetting because Matthew already feels bad and the needles make him feel worse," said Mrs. Loibl. "I saw something about this technology and said, `Let's get on with it."'