Proteolipid protein 1 (PLP1) plays a fundamental role in myelin sheath maintenance and oligodendrocyte development in the central nervous system. Through an alternative splicing process, the 7-exons-containing transcript (NM_000533.5) also produces a shorter isoform (DM20) that includes only exon 3A, whereas PLP1 includes exons 3A and 3B. Variants causing decreased PLP1 transcript levels are associated with features of hypomyelination of early myelinating structures. Antisense oligonucleotides (ASOs), small, single-stranded pieces of modified nucleic acids, can be used to modulate splicing and design disease-modifying drugs for this condition.A deep intronic variant (c.453+159G>A) was found to reduce PLP1 levels and skew the PLP1 to DM20 splicing ratio.ASOs were directed at the internal splice donor site (exon 3A) to drive the preferential use of the downstream PLP1 donor site (exon 3AB) resulting in exon 3B inclusion. This approach would be suitable as a strategy to target multiple variants hindering the inclusion of the PLP1-specific exon. Additionally, we targeted the intronic variant to assess whether ASOs binding the intronic secondary structure could alter the splicing ratio. As PLP1 expression is tissue-dependent, we generated oligodendrocytes-like cells differentiated directly from fibroblasts. ASOs were tested in this in vitro system to determine their ability to increase the expression of the PLP1 transcript. Preliminary results show promising effects of both approaches on the inclusion of exon 3B and a shift of the PLP1/DM20 ratio at the RNA level. The ASOs will be further tested in multiple patient-derived lines to confirm the restoration of ensheathment capacity after treatment.