As the substance patent for Takeda Pharmaceutical of Japan's potassium-competitive acid blocker (P-CAB) "Voquezna (ingredient name vonoprazan)" nears expiration, the domestic market has entered an inflection point.
There is an outlook that the market landscape could be shaken as the likelihood grows that a large number of generics will flow into the P-CAB market, which has grown around homegrown new drugs, all at once. In particular, the burden has increased for Daewon Pharmaceutical, which is preparing to launch a new drug around the same time.
According to the pharmaceutical industry on the 19th, traditional pharmaceutical companies such as Mothers Pharmaceutical, Kyongbo Pharmaceutical, Samik Pharm, and Dongkwang Pharm have already secured approvals for Voquezna generics. Dongwha Pharm is also awaiting approval, raising the likelihood that multiple generics will be launched simultaneously in time with the patent expiration.
The industry says, "Given the precedent in the gastroesophageal reflux disease treatment market where proton pump inhibitor (PPI) generics spread rapidly, P-CABs could show a similar trend."
Voquezna was approved in Japan in 2014 under the name "VONVANTY" as the world's first P-CAB new drug. It was subsequently approved by the U.S. Food and Drug Administration (FDA) in 2022 and has effectively dominated the U.S. P-CAB market.
In Korea, it received approval in 2019 but its launch was delayed due to pricing issues; recently, a decision was made to reenter the market in light of its growth potential. Voquezna's substance patent is scheduled to expire in the second half of 2028.
Accordingly, in 2028, an "overcrowded market" is expected to materialize as the original and numerous generics join the existing three-strong structure.
The current domestic P-CAB market is built around a "three-strong structure," including HK inno.N's "K-Cab (tegoprazan)," Daewoong Pharmaceutical's "Fexuclu (fexuprazan)," and Onconic Therapeutics' "Ja Q Bo (jastaprazan)."
These new drugs each maintain substance patents until 2031 and 2040 and are building defensive walls with additional patents. They have also begun full-fledged entries into global markets such as the United States and China, seeking external growth.
This environmental shift is weighing more heavily on latecomer new drug developers. Notably, "DW-4421 (padoprazan)," which Daewon Pharmaceutical is developing, faces unavoidable head-to-head competition with generics from the time of launch.
The substance was introduced from Unovia, a subsidiary of Ildong Pharmaceutical, with the target for completing phase 3 set for Feb. 2028. Considering the subsequent approval process, the actual launch timing is highly likely to overlap with Voquezna generics. From the outset, it would have to contend simultaneously with existing new drugs and low-priced generics.
However, many in the industry say that regardless of clinical results, actual market establishment is uncertain. An industry official said, "Unlike in the past, market establishment is not guaranteed just because it is a new drug," and added, "If the launch timing overlaps with generics, companies will have to redraw their overall strategies for securing prescriptions as well as on pricing competition."
Accordingly, the core of future P-CAB market competition is expected to shift to label expansion, formulation differentiation, and superiority in clinical data. Daewon Pharmaceutical is conducting a phase 3 trial to verify efficacy in treating erosive and non-erosive gastroesophageal reflux disease, and is also pursuing a phase 1 combination therapy for Helicobacter pylori eradication and an expansion to the indication for preventing nonsteroidal anti-inflammatory drug (NSAIDs)-induced peptic ulcers.
However, the gap with homegrown new drugs that have already secured the market is not small. K-Cab has built the broadest prescription base by securing five indications, including erosive and non-erosive gastroesophageal reflux disease. Fexuclu has three indications including erosive disease, and Ja Q Bo is also expanding its market focusing on indications for erosive disease and gastric ulcer. All are conducting additional studies to expand indications.
A Daewon Pharmaceutical official said, "In the previous phase 2 trial for patients with gastroesophageal reflux disease (GERD), padoprazan demonstrated treatment rates at week 4 and week 8 that were at least non-inferior to K-Cab, Fexuclu, and Ja Q Bo," and added, "By securing diverse indications, it will become a new treatment alternative for patients."