With the increase in drug development studies for rare diseases, gene therapies have recently come to the fore more frequently. In addition to orphan drugs used in the treatment of rare diseases, advanced therapy medicinal products have been developed. Advanced therapy medicinal products are a fast-growing field. Although it is not a treatment method used only in the field of rare diseases, it is also used in the fields of oncology and cardiovascular diseases, musculoskeletal diseases. Regenerative medicine can be promising in cases where advanced therapy medicinal products are difficult and clinically uncertain. There are various cell therapies related to regenerative medicine and cell-based therapies are one of them. Gene therapies, cell-based therapies, advanced therapy medicinal products and regenerative medicine products have high producer price and high production cost. Because all these treatments have limited clinical evidence and high costs, they are difficult to evaluate in terms of health technology assessment (HTA), and special considerations are needed for evaluation. As a solution, costs should be limited and clinical developments should be provided in cooperation with the society. SAVE (equivalent to young life saved) is recommended to evaluate the lifetime health profiles of curative treatments such as gene therapies. In order to reduce the budgetary burden of gene therapies, outcome-directed entry agreements with income-based payments are recommended. Compulsory use of gene therapies and non-reimbursement of these drugs can lead to catastrophic health expenditures. Various payment methods are offered to avoid catastrophic health expenditures. Income-based payment and outcome-based payment are some of these methods. It is also advocated that high prices should be accepted by the society, since gene therapies to be applied in the treatment of rare diseases will be applied to a small population. Both the support of the society to accept the high price of gene therapies, the support of the producer and the support of the payer are important in the development of gene therapies and their supply to the market.