A new drug is giving new hope to a London teen battling a rare and serious metabolic disorder.

Stefan Gacic is 14 and love sports, "I'm a huge fan of the Leafs and Jays - I like soccer."

He regularly beats his mom Verica Gacic at ping pong, but outside of sports Stefan faces a very formidable adversary - Morquio A syndrome.

Verica explains "It's progressive...by the age of six [or] seven he had spine surgery."

The syndrome is a very rare condition affecting less than 100 Canadians. Typically, it presents a number of health challenges impacting mobility as well as heart and lung function.

Dr. Chitra Prasad, a medical geneticist with Children's Hospital, explains the illness.

"It's a genetic disorder causing problems of enzyme deficiency and then affecting the whole body, but the brain is not involved."

The first symptoms appeared when Stefan was two. At first the disease progressed slowly until the he turned 10, Verica says.

"We had a step in front of the house and he even had a hard time stepping up. So many ear infections, so many chest infections and pain in the joints."

Stefan was part of a clinical trial for the enzyme-replacement drug vimizim, which - although it's not a cure - offers hope.

"It's a very big start because getting into the bone is not easy for any of the enzyme-replacement therapies," Prasad says.

Stefan will continue to receive the drug as part of the trial, but the family hopes the province will help cover the cost for others.

According to the manufacturer, Biomarin, the price has not yet been set in Canada.

Verica says it's really made a difference, "Now he's full of energy again. Again he's that personality - go, go, go - and now I think we're back on track."

Stefan meanwhile is looking forward to going to high school in the fall.

"It's going to be hard going class to class because of all the floors and all that, but yeah [I'm] excited."

And Verica is enjoying every milestone, "He just had his [Grade 8] graduation and he walked to the stage to get his diploma - I was so proud of him."