[Edaily Reporter NA EUN-KYUNG ] #G2GBIO, Inc., a developer of long-acting injectable drugs, is expanding its business scope into ultra-high-concentration subcutaneous (SC) antibody formulations. At the core of this expansion is the “InnoBioLAMP” platform, which utilizes microparticle manufacturing technology to encapsulate antibodies at high concentrations while maintaining injectable viscosity.

G2GBIO, Inc. has confirmed the injectability of its formulation at a concentration of approximately 750 mg/mL. However, as this is still an early-stage technology in the laboratory phase, further validation—including application to actual therapeutic antibodies and preclinical and clinical trials—remains to be conducted. The company has signed a business agreement with the Celltrion(068270), including a Material Transfer Agreement (MTA), to verify the feasibility of applying the technology to antibodies.

Lee Hee-yong, CEO of G2GBIO, Inc., stated in an interview with Edaily on the 30th, “If microparticle technology was G2GBIO, Inc.’s first growth driver, the subcutaneous (SC) antibody formulation is the growth driver for our second leap forward.” He added, “To develop actual therapeutic antibodies into ultra-high-concentration SC injections, we must naturally undergo preclinical and clinical trials. “We have already completed a significant portion of the laboratory-scale research that can be conducted prior to that, and we plan to ultra-concentrate various antibodies in accordance with our future schedule,” he added.

High-concentration IV doses in SC syringes

Antibody drugs generally require large doses and have large molecular sizes, so

they

are administered via intravenous (IV) injection. To convert these to subcutaneous (SC) formulations, the antibody concentration must be significantly increased to fit the existing dose into a limited injection volume.

The problem is that as antibodies are highly concentrated in their liquid state, intermolecular interactions increase, causing viscosity to rise sharply. This can lead to “loss of syringeability,” making it difficult for the solution to pass through the syringe needle, and there is also a risk of reduced stability due to protein aggregation or self-association.

G2GBIO, Inc.’s strategy to overcome these limitations involves converting the antibody into microparticles and dispersing them in a non-aqueous carrier. The company explained that when a suspension formulation with a concentration of 750 mg/mL was administered using a 27-gauge needle, the injection force recorded was approximately 14 N—lower than the standard injection force of 20 Newtons (N). This means the formulation can be administered via a syringe with minimal force.

CEO Lee explained, “Achieving high concentrations is a key competitive advantage of subcutaneous antibody formulations,” adding, “If the antibody cannot be concentrated, the injection volume becomes excessively large, making subcutaneous injection difficult; ultimately, the antibody must be diluted and administered intravenously.”

However, the 750 mg/mL result is an initial study finding demonstrating the injectability of the current platform. G2GBIO, Inc. plans to gradually verify the formulation’s applicability, quality, and efficacy using actual therapeutic antibodies in the future. The company also aims to expand its scope of application beyond monoclonal antibodies to include bispecific antibodies, antibody-drug conjugates (ADCs), and Fc fusion proteins.

Halozime Also Secures Microparticle Technology… Global Competition Heats Up

G2GBIO, Inc. is not the only company developing subcutaneous (SC) antibody formulation technology using microparticles. In South Korea, Inventage Lab Inc.(389470)has previously unveiled its microfluidics-based “IVL-Biofluidic” platform. Overseas, Electropie is recognized as a leader in this field after developing “Hypercon,” a platform for ultra-high-concentration microparticle formulations.

In particular, Halozyme, which possesses hyaluronidase-based SC formulation technology, acquired ElectroPhy last year for an upfront payment of $750 million (approximately 1 trillion won) and a total of up to $900 million (approximately 1.3 trillion won), including milestone payments upon approval. In addition to the existing method of temporarily expanding the subcutaneous space to inject large amounts of drug, the company has now secured technology that reduces the volume of administration by highly concentrating the antibody itself. This can be seen as a case that validates the commercial value of the ultra-high-concentration SC platform.

G2GBIO, Inc. highlights compatibility with existing microparticle processes for long-acting injectables as a key differentiator. The company explains that this reduces the burden of building a separate, dedicated antibody production line from scratch and allows experience in microparticle production to be leveraged in large-scale manufacturing processes. However, to demonstrate the feasibility of actual commercial production, the company must sequentially complete joint research, process optimization, and preclinical and clinical trials.

CEO Lee emphasized, “What we are developing is not just a formulation, but a technology that gives patients back their time,” adding, “We will expand opportunities for collaboration with global pharmaceutical companies—including technology transfer and joint development—to ensure that our accumulated technological capabilities translate into actual business results and revenue.”