A drug that has been successful in treating a rare, deadly parasitic infection has been made available to a Houston teen who is battling the brain-eating amoeba, the Centers for Disease Control and Prevention confirmed.
The teenager, 14-year-old Michael Riley Jr., remains hospitalized with primary amebic meningeoencephalitis (PAM), a brain infection caused by the amoeba Naegleria fowleri. The condition is nearly always fatal.
Doctors treating Riley obtained the drug, miltefosine, which is normally used to treat another parasitic disease found in the tropics called leishmaniasis. Researchers found that it also showed promise in the lab for treating other free-living amoeba (FLA) infections, including those caused by Naegleria fowleri.
The Centers for Disease Control and Prevention has been providing the drug to doctors, with permission from the FDA, since 2009.
The CDC says miltefosine, along with other medications and therapies, helped save Kali Hardig, a 12-year-old Arkansas girl who was diagnosed with PAM in 2013. Hardig was the first patient since 1979 to survive the infection.
That same summer, a second child who was treated with miltefosine also survived, but suffered brain damage.
But experts warn the drug is not a magic bullet.
"That summer that we had the two survivors, including the girl from Arkansas, we very closely analyzed what happened there," Dr. Jennifer Cope, a medical epidemiologist with the CDC, told CBS News. "In the end we think it was probably a multifactorial 'perfect storm' of everything that happened to come together and have that perfect outcome."
Cope noted that miltefosine is not the only drug that's given to treat this type of infection.
"It's actually a full cocktail of drugs that are recommended, and miltefosine - the one that we have in Atlanta - is just one part of that. So the other drugs can be given as soon as they can be ordered from the hospital pharmacy," said Cope. "And then this one ... they make contact with us and order it here from Atlanta and we get it out as quickly as we can."
Until recently, miltefosine was only available from Germany. It is now one of several drugs used to treat rare diseases that the CDC keeps onsite in Atlanta.
A CDC blog notes that in 2014, the CDC sent 14 shipments of miltefosine to doctors treating possible FLA infections. The drug remains under an FDA investigational treatment program for FLA infections.
The amoeba Naegleria fowleri is found in warm freshwater like lakes and rivers, and can cause infections when it gets into a person's nose and travels to the brain. In Michael Riley's case, he's believed to have contracted the illness after swimming with friends at a lake in Sam Houston National Forest on August 13.
Riley is reported to be in a medically induced coma at Texas Children's Hospital, where doctors recognized the infection from having recently treated another case in the area. That patient died.