Objectives – To examine if HIV nosode in 30c dilution (HIV 30c) has therapeutic potential against lung cancer cells (A549) as compared to WRL-68 normal cells and to elucidate its possible molecular mechanism of action on DNA replication and apoptosis. Methods – Effects of HIV 30c were thoroughly tested for its possible anticancer potential on A549 cells (lung cancer); WRL-68 normal liver cells served as control. Three doses, one at LD50 and two below LD-50, were used. Proliferation, migration and senescence assays were made and generation of reactive oxygen species (ROS) studied by routine techniques. The ability of HIV 30c to induce apoptosis in A549 cells and its possible signalling pathway were determined using immunoblots of relevant signal proteins and confocal microscopy, including studies on telomerase reverse transcriptase (TERT) and topoisomerase II (Top II) activities, intimately associated with cell division and DNA replication. Results – HIV 30c prevented cancer cell proliferation and migration, induced pre-mature senescence, enhanced pro-apoptotic signal proteins like p53, bax, cytochrome c, caspase-3 and inhibited anti-apoptotic signal proteins Bcl2, TERT and Top II, changed mitochondrial membrane potential and caused externalization of phosphatidyl serine. Thus, it induced apoptosis as also evidenced from increase in cells with distorted membrane morphology, nuclear condensation, DNA fragmentation, and ROS, typical of apoptosis in progress. Conclusion – HIV 30c nosode has therapeutic potential for inducing cytotoxic effects on A549 cells as manifested by changes in nuclear condensation, DNA fragmentation, ROS generation and MMP, and for its inhibitory action on cell proliferation, cell migration, expression of telomerase reverse transcriptase and Top II genes, and increasing expression of pro-apoptotic genes.