Biopharma iBio, Inc. (NYSEA:IBIO) has entered into a definitive global exclusive license agreement with RubrYc Therapeutics for RTX-003, an immunotherapy candidate targeting regulatory T cells. In addition, the deal includes an option for iBio to license additional antibodies designed with RubrYc’s antibody discovery platform based on machine learning and computational biology.
iBio made an upfront $5 million payment to RubrYc for the rights and has committed to an additional $2.5 million payment in December 2021. iBio will have the rights to commercialize RTX-003 and has retained options for other molecules developed with RubrYc’s predictive algorithms. The deal also includes an equity stake. RubrYc is eligible to receive certain pre-specified payments upon achievement of development milestones for IBIO-101, as well as royalties on net sales of that molecule and other licensed antibodies.
RTX-003 binds to interleukin-2 (IL-2) receptor alpha chain (CD25) without interfering with the IL-2 signaling pathway. Enabling that functionality is “a widely recognized challenge,” said Tom Isett, chairman and CEO of iBio, in a statement. The preclinical development of RTX-003 thus validates the functionality of RubrYc. “Moving forward, we aim to replicate this discovery and development model by combining access to the RubrYc Discovery Platform with iBio’s proprietary Glycaneering and FastPharming Technologies to bring multiple new candidates to the clinic in a timely and cost-efficient manner,” he added.
iBio’s FastPharming uses a plant-based system rather than a traditional mammalian system.

Image courtesy of iBio
“By avoiding lengthy cell-line engineering requirements of traditional mammalian cell bioprocessing, FastPharming enables more candidates to reach early preclinical and IND-enabling studies faster,” said iBio Chief Operating Officer Randy Maddux. “The time and money saved on early development ultimately gets the right candidate to the clinic sooner, and in a more sustainable production system than traditional methods.”
iBio says FastPharming technology can yield a few milligrams of material for feasibility testing in approximately five weeks.
The GMP scale-up process for FastPharming uses bacteria for the engineering and qualification of the master cell bank. With the mammalian process, the engineering, qualification and GMP production times are longer, according to iBio.
As opposed to traditional cell-culture bioprocesses that are often performed using plastic, single-use bioreactor systems, iBio’s FastPharming System uses plants as bioreactors.
A plant-specific expression vector with the gene of interest is transfected into Agrobacterium, which is then vacuum-infiltrated into the leaves of the company’s proprietary Nicotiana benthamiana plants, which is a tobacco relative. The target protein is expressed in the leaves as the plants grow. The company then harvests the leaves, and isolates and purifies the protein. It can then be formulated into the desired final product.
RubrYc Therapeutics created RTX-003 to induce T regulatory cell death to enhance the immune response to tumors. Increased T reg cells or decreased active T cells in a tumor are linked with reduced overall survival and progression-free survival in various tumors.
iBio plans to bring RTX-003 to the clinic as IBIO-101, using its FastPharming System to produce the drug candidate.
The company hopes to launch IND-enabling studies by mid-2022.
Filed Under: clinical trials, Drug Discovery, Oncology