Three Korean companies rename Vemlidy generic products

Dong-A ST changes product name from ‘Vemlia’ to ‘Tafria’

Samil completes change to ‘Teno-S,’ Daewoong to ‘Tafvir’

Supreme Court upholds ruling against generic manufacturers in Vemlidy trademark case

Daewoong Pharmaceutical, Dong-A ST, and Samil Pharmaceutical have consecutively changed the brand names of their generic versions of the hepatitis B treatment ‘Vemlidy (tenofovir alafenamide).’ The move is interpreted as the result of their final defeat in a trademark dispute with the originator company that reached the Supreme Court.

According to industry sources on June 23, Dong-A ST changed the name of its product from ‘Vemlia Tab’ to ‘Tafria Tab’ effective June 22. On the same day, Samil Pharmaceutical changed ‘Vemlino Tab’ to ‘Teno-S Tab.’ Earlier, on June 16, Daewoong Pharmaceutical changed ‘Vemliver Tab’ to ‘Tafvir Tab.’

As a result, three Vemlidy generics have undergone brand name changes one after another. The changes stem from the companies’ final defeat in a trademark dispute with the original manufacturer.

Photos of Dong-A ST’s Vemlia, Samil Pharmaceutical’s Vemlino, and Daewoong Pharmaceutical’s Vemliver. The products have been renamed Tafria, Teno-S, and Tafvir, respectively.

In July 2023, originator company Gilead Sciences filed trademark invalidation actions against the three companies, approximately four months after the generics received marketing approval. Gilead argued that the three-syllable element “Vemli” that appears in both the originator product Vemlidy and the three generic product names could cause trademark confusion.

In April last year, the Intellectual Property Trial and Appeal Board ruled in favor of the generic manufacturers. The board concluded that, given the nature of prescription drugs prescribed and dispensed by healthcare professionals such as physicians and pharmacists, the likelihood of confusion or misunderstanding is low, and that the trademark should be perceived as a distinct coined term.

Gilead appealed the decision to the Patent Court. In February this year, the Patent Court overturned the earlier ruling, finding that the generic product names were similar to the originator brand name and could create confusion.

Following their loss in the second instance court, the generic manufacturers appealed to the Supreme Court. On the 11th, the Supreme Court dismissed the appeals without substantive review. This court’s dismissal without merit refers to a process where the Supreme Court upholds the lower court’s judgment without reviewing the case on its merits.

Following their final defeat, the generic manufacturers had little choice but to change their product names, as continuing to market the products under the disputed names could be interpreted as trademark infringement. This ultimately led to the successive rebranding of all three products.

The three companies now face the challenge of rebuilding brand recognition from scratch. They had spent nearly three years marketing the products under their previous names and establishing awareness among prescribers. In addition, the companies must undergo a series of administrative procedures, including changing product names in MFDS-approved labels, revising names on HIRA’s reimbursement listings, and replacing packaging materials and package inserts already in circulation.

The pharmaceutical industry's attention is now focused on whether the other generic products, which did not adopt the 'Vemli-' prefix from the beginning, will benefit from this outcome. These include Chong Kun Dang’s Tenofobell-A, Hutecs Korea’s ‘Ganelid,’ Dongkook Pharmaceutical’s ‘Alfoterin,’ Samjin Pharmaceutical’s ‘Taflead,’ and Jeil Pharmaceutical’s ‘ Tecavir-D Tab.’ Gilead has not filed for the invalidation of the trademark rights for these products.

Coincidentally, the three companies that lost the trademark dispute had held the top three prescription rankings among Vemlidy generics. According to pharmaceutical market research firm UBIST, the 2025 prescription sales of Samil Pharmaceutical’s Vemlino (rebranded as Teno-S) increased by 59% YoY to KRW 3.8 billion, Dong-A ST’s Vemlia (rebranded as Tafria) by 66% to KRW 2.9 billion, and Daewoong Pharmaceutical’s Vemliver (rebranded as Tafvir) by 93% to KRW 1.3 billion. In contrast, all remaining competing products recorded annual prescription sales of less than KRW 500 million.

Vemlidy is a novel hepatitis B treatment developed by Gilead as the successor to Viread. Although Viread demonstrated strong antiviral efficacy against the hepatitis B virus, concerns remained regarding side effects such as renal impairment and reductions in bone mineral density. Vemlidy was developed to address these shortcomings. Clinical studies showed no significant occurrence of renal dysfunction or bone mineral density loss. The defining strength of this treatment lies in its proven long-term safety, given the chronic nature of hepatitis B and the need for prolonged treatment.

Among major originator hepatitis B therapies, Vemlidy remains the only product that continues to grow. Prescription sales reached KRW 76.9 billion last year, an 8% increase YoY. In the first quarter of this year, sales rose 12% YoY to KRW 19.8 billion.