RELIEF THERAPEUTICS Holding SA Announces Divestment of its Subsidiary Relief Therapeutics SA to Sonnet BioTherapeutics, Inc. to Ensure the Development of Atexakin Alpha (Interleukin-6)

12 August 2019
  • The SIX-listed group RELIEF THERAPEUTICS Holding SA divests its subsidiary Relief Therapeutics SA to Sonnet BioTherapeutics Inc. (“Sonnet”).
  • Sonnet commits to develop atexakin alfa initially licensed to Relief Therapeutics SA from Merck KGaA, fo™r the treatment of Peripheral Neuropathies.
  • Sonnet is engaged to initiate, in addition to the clinical development of atexakin alfa, the non-clinical development of its portfolio of innovative biologics based on the company’s Fully Human Antibody Binding (FHABTM) Technology.
  • Sonnet has access, through an experienced investor, to a certain common stock purchase agreement, implementing an equity facility of up to $100 million, which will be used to progress atexakin alfa and Sonnet’s proprietary portfolio of experimental drug candidates. Other funding sources are also actively being pursued.
  • The overall transaction aims to create a world-class, clinical-stage, biopharmaceutical company focusing on the development of a portfolio of innovative drug candidates for cancer and cancer-related complications

GENEVA, August 12, 2019

RELIEF THERAPEUTICS Holding SA (SIX-RLF, “Relief” or the “Company”) announces today that it has executed a binding Share Exchange Agreement (the “Agreement”) with Sonnet BioTherapeutics, Inc. (“Sonnet“). Sonnet is a privately held, oncology-focused biotechnology company developing targeted biologic drugs based on their innovative Fully Human Albumin Binding (“FHAB™”) platform. With this Agreement, Sonnet will acquire, providing certain condition precedents are met, all outstanding shares of the subsidiary of Relief, i.e. Relief Therapeutics SA.

Relief Therapeutics SA has executed, on 28 August 2015, a license agreement with Ares Trading SA, a wholly-owned subsidiary of Merck KGaA (“Merck”), for the exclusive, worldwide right to research, develop, use and commercialize atexakin alfa (“Atexakin”, or the “Molecule” or “SON-080” or the “Asset”). Atexakin is a low-dosage formulation of interleukin-6 (IL-6), a natural mammalian cytokine of 185 amino acids with pleiotropic functions in different tissues and organs for which clinical Phase I/II studies were conducted in thrombocytopenic cancer patients by Serono International (“Serono”), later acquired by Merck. Additional pre-clinical results generated by Serono in specific animal models have demonstrated the ability of Atexakin to regrow nerves and reinstate their normal functions, suggesting its potential to treat a cluster of diseases referred to as neuropathies. Furthermore, based on precedent clinical investigations in different settings involving hundreds of patients documenting the safety of the Molecule at the dose intended to be used, Sonnet is committed to fund and pursue the development of Atexakin in Chemotherapy Induced Peripheral Neuropathy (“CIPN”). The Asset could also be extended to other diseases, in particular Diabetic Neuropathy.

The terms of the Agreement include payment to Relief of 7,111,947 common shares of Sonnet out of the aggregate total number issued and outstanding common stock as of the date of this Agreement.  Upon closing, Sonnet will immediately assume the development of SON-080 together with its proprietary experimental drugs.  The Agreement, subject to normal closing conditions, is expected to close at the time that Sonnet becomes a publicly traded corporation.

At the closing of the transaction, Sonnet is expected to be well positioned with financing to develop not only Atexakin, but also to move forward Sonnet’s proprietary FHABTM technology, which has the potential to deliver safer, more effective anti-cancer treatments.

The acquisition of Relief’s subsidiary by Sonnet well positions the Atexakin development program by propelling it forward towards the market with the ultimate goal of hopefully positively transforming the lives of affected patients” commented Raghuram (Ram) Selvaraju, PhD, MBA, Chairman of Relief.  “We are excited about the opportunity to work with the Sonnet team, which brings extensive drug development expertise and will add supplementary value to that brought by the previous developments of the Asset.”

After carefully reviewing the preclinical and clinical data, we believe Atexakin has the potential to be a safe and effective treatment for CIPN, where there are currently no approved disease modifying therapies” commented Pankaj Mohan, PhD, Chairman of Sonnet.  “Owing to the size of the patient population and corresponding high unmet medical need, we see Atexakin as having the potential to eventually become a blockbuster product. We are excited to integrate it into our existing pipeline of oncology assets.”


Relief is a company developing drugs via participation in active entities that have obtained intellectual properties through their own research activities or via in-licensing. Development activities of Relief group of companies focus primarily on clinical-stage projects based on molecules of natural origin (peptides and proteins) with a history of clinical testing and use in human patients or a strong scientific rational. Currently, Relief is concentrating its efforts on developing new treatment solutions for indications related to diabetic complications and respiratory diseases.

About Sonnet BioTherapeutics, Inc.

Founded in 2011, Sonnet BioTherapeutics, Inc. is an oncology-focused biotechnology company with a proprietary platform for innovating biologic drugs of single- or bi-specific action. Known as FHAB™ (Fully Human Albumin Binding), the technology utilizes a fully human single chain antibody fragment (“scFv”) that binds to and “hitch-hikes” on human serum albumin (“HSA“) for transport to target tissues. FHAB™ is the foundation of a modular, plug-and-play construct for potentiating a range of large molecule therapeutic classes, including cytokines, peptides, antibodies and vaccines.

About Chemotherapy Induced Peripheral Neuropathy

Chemotherapy Induced Peripheral Neuropathy (“CIPN”) is a progressive degeneration of nerve fibers resulting from chemotherapy. It is a debilitating condition for which there are currently no approved treatments. Symptoms of CIPN include pain, motor weakness, loss of sensory perception at the extremities and autonomous nervous system impairment. It is estimated that over 50% of cancer patients receiving chemotherapy develop CIPN and that the condition persists in over 50% of cancer survivors.

RELIEF THERAPEUTICS Holding SA is listed on the SIX Swiss Exchange under the symbol RLF.

Damien Conus, Partner, CPV Partners, Geneva, led the legal team that represented Relief in this transaction. Rajiv Khanna, Shareholder of, and Dan Richey, Associate of Buchannan Ingersoll & Rooney PC, New York, led the legal team that represented Sonnet in this transaction.

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This communication expressly or implicitly contains certain forward-looking statements concerning RELIEF THERAPEUTICS Holding SA, Sonnet BioTherapeutics, Inc. and their business. Such statements involve certain known and unknown risks, uncertainties and other factors, which could cause the actual results, financial condition, performance or achievements of RELIEF THERAPEUTICS Holding SA and/or Sonnet BioTherapeutics, Inc. to be materially different from any future results, performance or achievements expressed or implied by such forward-looking statements. RELIEF THERAPEUTICS Holding SA is providing this communication as of this date and does not undertake to update any forward looking statements contained herein as a result of new information, future events or otherwise.