PERMANENT TREATMENT FOR PKU: GEN THERAPY

Gene therapy for PKU patients is still in clinical study. Successful results have been achieved on animals, but studies on humans are very limited. American Gene Technology (AGT) continues its studies for safe, effective and cost-effective genetic treatments for PKU patients.

What Is Gene Therapy?

PKU patients cannot produce the enzyme called "FAH" due to a defect in    the genes in the liver cells. This enzyme takes part in the conversion of the amino acid called            "phenylalanine" in proteins to another amino acid called "tyrosine". Gene therapy: It modifies this defective gene located in the liver cell. it adds the gene that will produce the enzyme "FAH" to the DNA of the individual with PKU, and blocks the defective part of the patient's gene. Thus, “FAH” enzyme is provided to be produced perfectly. It is ensured that “phenylalanine” taken with foods is converted into “tyrosine” without the need for dietary restrictions, and the individual is returned to normal nutrition. The added gene integrates into the liver cell. This means that the added gene makes its own copy in each cell division. Thus, a permanent solution is provided, regardless of lifelong injection and drug treatment.

Why Is Gene Therapy Difficult?

Although gene therapy eliminates treatment for life, there are some difficulties in developing the treatment. Research shows that there are more than 500 mutations in the gene that causes Phenylketonuria. This means modifying more than 500 genes. This makes gene therapy very difficult and complex.

Which Stage Is the Work Done?

Biopharma, a Rare Diseases Drug Company, released its first clinical data for PKU gene therapy in December 2019. In the study titled “HMI-102” which includes 21 adult individuals between the ages of 18-55 with PKU, 2 patients receive gene therapy at the lowest dose and one at a higher dose. Patients will be monitored for 1 year and their blood levels of "phenylalanine" will be monitored. The data obtained showed that while the two subjects receiving low doses did not experience a decrease in blood phenylalanine levels, the amount of “phenylalanine” in the blood of the third patient who received the higher dose decreased while the “tyrosine” levels increased. The researchers, who stated that this study is still in its early stages, noted that there is a potential to increase the dose of therapy in the future, and that the small amount of data currently available is promising for successful results in gene therapy. Stating that another phase study for gene therapy will begin in early 2020, the researchers announced that they will share new information about the study in the middle of 2020. Stating that it is too early to conclude about the usefulness of the treatment, experts noted that the studies were a step forward for the treatment of rare hereditary conditions.

Gülşah Kurtoğlu

Food Engineer