Well, yeah basically. Telomerase is a reverse transcriptase that uses RNA as a template for coding DNA segments. The whole thing revolves around repairing chromosomes, or at least the ends. Every time a chromosome replicates, the telomeres on the ends get shorter (apparently, at a point the shortness tells the cell to stop dividing) - IOW, this controls the "aging" of most cells. After x number of replications, the cells die. Cells with telomerase are essentially immortal. Germline cells, some single-cell eukaryotes, and some cancer cells manufacture telomerase.
All you need to do is figure out some way to develop an injectable, temporary telomerase gene into your existing chromosomes, and voila! Immortality.