In March 2026, the Global Antibiotic Research and Development Partnership (GARDP) announced that it would restart development of apramycin, an antibiotic program that had stalled after Swiss biotechnology company Juvabis AG closed in 2025. GARDP acquired the program’s data and rights for human use, together with an exclusive license through the University of Zurich, and announced plans for a phase I multi-day dosing study expected to begin in 2027. Subsequent requests for proposals covering pharmacokinetic assay work and a hospital-based clinical trial demonstrated that the program had moved beyond asset acquisition toward renewed development.1,2
The case illustrates an important distinction in antimicrobial resistance (AMR) innovation. A company can fail without its antibiotic having failed scientifically. The economics surrounding new antibacterial drugs have repeatedly placed developers under severe financial pressure, including companies that successfully advanced products through regulatory approval. Achaogen, which developed and launched plazomicin, filed for Chapter 11 bankruptcy protection in 2019, less than a year after the product entered the U.S. market.3–5
Considerable attention has focused on why the antibiotic market produces these outcomes and how incentives might make development more sustainable. A different problem begins once financial distress has already occurred: whether a promising antibiotic can be separated from the corporate failure surrounding it.
Apramycin shows that this is possible. Other transactions show that doing so may require preserving far more than ownership rights. Regulatory responsibilities, technical records, supply relationships, safety systems, and continued development funding may all need to remain available long enough for another organization to take control.
That creates a distinct challenge for the AMR ecosystem. If a developer fails, what mechanisms can preserve a valuable program until an appropriate new steward is ready to assume it?
The Antibiotic Rescue Window
The 2026 winding up of Iterum Therapeutics illustrates how narrow the opportunity for an orderly transfer can become. Before filing its winding-up petition, Iterum had been discussing a potential acquisition of sulopenem with two prospective counterparties. According to the company, neither was able to finalize and consummate a transaction on the required terms and timeline, given Iterum’s limited remaining cash runway. The company proceeded into liquidation, although its liquidators retained the possibility of selling some or all of its assets afterward.6
The case suggests the existence of an antibiotic “rescue window”: the finite interval during which a distressed developer still has enough organizational and financial continuity to execute a transfer. The term is not a formal regulatory or financial designation, but it captures a practical issue visible in other antibiotic transactions. A potential successor may exist, yet the seller still must remain functional long enough to complete due diligence, negotiate terms, maintain required activities, and deliver the information and assets the successor needs.
The agreements surrounding other transfers show how much may have to remain in place during that interval. When Achaogen agreed to sell plazomicin assets to Cipla, its pre-closing obligations included maintaining regulatory documentation and records, making necessary regulatory filings and payments, preserving regulatory approvals, and maintaining important supplier and customer relationships.7 In the later transfer of lefamulin rights from Nabriva Therapeutics to Sumitomo Pharma, the parties created a formal Bridge Period during which Nabriva continued specified regulatory, pharmacovigilance, corporate, and transition activities after the transaction closed.8
These examples distinguish two related problems: identifying a successor and preserving the program long enough for that successor to assume responsibility.
The Iterum case suggests why rescue efforts may need to begin before liquidation. By the time the company filed to wind up, limited runway had already prevented two contemplated sulopenem transactions from reaching completion. For promising antibiotics, the timing of intervention may therefore matter almost as much as the identity of the eventual purchaser.
An Antibiotic Is More Than Its Patent
The bankruptcy sale of Achaogen provides an unusually detailed view of what an antibiotic transfer can involve. Cipla acquired worldwide plazomicin rights outside Greater China through a structured asset sale, but the transaction encompassed far more than patents and trademarks. The underlying agreement included know-how, manufacturing and production processes, research and development information, clinical-trial data, safety and pharmacovigilance information, supplier information, databases, technical documentation, and other records connected with the product.7,9
The purchased assets also included regulatory authorizations and correspondence, product inventory, quality-control records, standard operating procedures, supplier and vendor information, production records, and other books and records.
The later Nabriva transaction offers an even more granular view. Product records associated with lefamulin included characterization and stability reports, batch records, raw-material and finished-product specifications, manufacturing manuals, process-validation reports, analytical-method documentation, quality-control procedures, laboratory-notebook data, and vendor and supplier records. Physical and electronic laboratory notebooks received specific provisions governing their transfer and temporary retention during the transition.
These materials document the history of how a product has been developed, manufactured, analyzed, controlled, studied, and discussed with regulators. A successor that receives an incomplete version of that history may face a substantially more difficult task than one that receives the full technical and regulatory package assembled by the original developer.
This makes rescue fundamentally different from purchasing a patent portfolio. The asset being preserved is a combination of rights, records, responsibilities, physical materials, and established relationships. The more completely that package survives the transition, the better positioned a new steward is to continue development or commercialization from where the former company left off.
Keeping Regulatory Continuity Intact
Drug ownership can change, but regulatory responsibilities must move with it.
In the United States, Food and Drug Administration (FDA) regulations expressly permit ownership of a drug application to be transferred. The former owner must notify FDA that its rights have been transferred, while the new owner must accept the existing agreements, promises, and conditions associated with the application and possess or obtain a complete copy of it.10
European Medicines Agency (EMA) guidance likewise addresses transfers when an existing marketing authorization holder is expected to cease to exist as a legal entity. Remaining enforceable post-authorization obligations become the responsibility of the transferee, and transitional arrangements define when those responsibilities move to the new holder.11
The Nabriva transaction shows what this can require operationally. During the bridge period, relevant Nabriva entities had to remain in existence, and specified U.S. and Chinese regulatory applications and approvals had to be maintained. Nabriva also continued coordinating regulatory interactions and providing information concerning ongoing studies, postmarketing requirements, correspondence, and the status of product development.
Pharmacovigilance required its own continuity. Nabriva was obligated to maintain the global safety database and coordinate pharmacovigilance activities during the transition. The purchaser therefore did not rely on an immediate cutover in which every regulatory and safety function shifted at closing. Instead, the agreement preserved those activities long enough to support an orderly assumption of responsibility.
Achaogen’s pre-closing obligations followed the same broad logic. The company had to maintain regulatory documentation and records, make necessary regulatory filings and payments, and preserve approvals required for the business until the transfer could be completed.
These cases make regulatory continuity part of the asset-rescue problem rather than a procedural task that can be addressed after ownership changes. A new steward needs not only legal rights to the product, but a current regulatory record and a workable path for assuming the associated obligations.
Preserving the Manufacturing Network
A stranded antibiotic may also depend on a manufacturing network that cannot simply be recreated at closing.
The Nabriva–Sumitomo transaction makes that issue unusually visible. Sumitomo agreed to a $15 million upfront payment for the transferred rights. Of that amount, $10.4 million was paid on Nabriva’s behalf to contract manufacturers associated with active pharmaceutical ingredient production, intravenous vials, tablets, and infusion bags.12
Those payments show that preserving the product required addressing obligations embedded in the existing supply chain. The transfer was not limited to obtaining legal rights and then arranging future manufacturing independently. Existing contract manufacturing organization (CMO) relationships had financial consequences that had to be resolved as part of the transaction.
Achaogen encountered a related issue during the plazomicin sale. Its agreement with Cipla specifically addressed an existing manufacturing arrangement with Hovione, including a release associated with that agreement and efforts by Cipla to negotiate a new supply arrangement.7
The technical package transferred with these products also matters because a successor must understand how the drug has been produced and controlled. The transferred records included manufacturing processes, specifications, validation information, analytical methods, batch documentation, supplier information, and other materials needed to understand the established process.
Actual rescue transactions therefore treat both documentation and the surrounding supplier network as material. A prospective steward may need to determine which existing relationships can be preserved, which obligations must be resolved, and where new arrangements must be established.
That consideration becomes especially important when a financially distressed company is reducing spending. Preserving an antibiotic may require enough support for the supply network to remain usable while another organization prepares to assume it.
Financing the Space Between Owners
The transition itself also requires capital.
Nabriva’s Bridge Period offers a concrete model. After closing, Nabriva agreed to continue supporting the transferred product for a defined period that could extend through March 2024 and, under specified circumstances, through September 2024. Sumitomo agreed to reimburse qualifying operating expenses up to an initial aggregate cap of $3 million, including $2 million provided at closing as prepaid expense reimbursement.
The structure highlights three distinct financial requirements that can otherwise become conflated. Acquisition capital pays for ownership or rights to the antibiotic. Continuity capital supports the temporary functions needed to bridge the transfer. Development capital pays for the work still required after the new steward assumes responsibility.
“Continuity capital” is not a formal category in these agreements, but it describes what the Nabriva arrangement accomplished. The purchaser funded a period during which the seller continued operating specified regulatory, safety, corporate, and transition activities rather than shutting them down immediately.
That middle category may be particularly important when financial distress precedes a completed transaction. The Iterum case shows that even discussions with potential successors may not produce a rescue if the seller lacks sufficient runway to reach closing.
Development-stage assets present an additional financing challenge because acquisition does not complete the program. GARDP’s acquisition of apramycin created the opportunity to restart development, after which the organization announced plans for additional clinical work and issued requests for proposals covering pharmacokinetic assays and a hospital-based clinical study.
Organizations capable of assuming such programs may draw on different financing structures from conventional biotechnology companies. GARDP receives support from multiple public and private funders, and ten funders committed €60.8 million in 2024 to its broader antibiotic research, development, and access activities. That funding was not announced specifically for apramycin, but it demonstrates the mixed funding base available to a nonprofit antibiotic developer.13
A rescue strategy therefore must consider not only who will ultimately own the asset but who will pay to preserve it until that transfer is complete and who will finance the work that remains afterward.
Finding a Steward Rather Than Merely a Buyer
The documented antibiotic rescues show that successor stewardship can take several forms.
One model is a straightforward asset sale. Cipla acquired plazomicin rights and associated assets from Achaogen through the bankruptcy process. (
Another is a staged or transitional transfer. Sumitomo acquired Greater China rights to lefamulin while financing an extended Bridge Period and resolving substantial CMO obligations. Rights to XENLETA outside Greater China later moved to HKF, which subsequently licensed U.S. commercialization rights to Meitheal Pharmaceuticals.8,12,14
A third model preserves the company itself. Melinta entered Chapter 11 under a restructuring agreement in which secured lenders would exchange $140 million in secured claims for ownership of the reorganized company. It emerged from Chapter 11 in April 2020 under Deerfield ownership and continued supplying and supporting four marketed anti-infective products.15,16
A fourth model places the program with a public-interest developer. GARDP acquired the apramycin program after Juvabis closed and assumed responsibility for restarting its clinical development.
Which model fits depends in part on what remains to be done. A marketed antibiotic with an established supply chain presents a different problem from an early-stage program requiring additional clinical trials. Territorial rights may be divided among different parties. In some situations, preserving the operating company may provide another route to maintaining continuity. In others, a nonprofit developer may offer a different pathway for advancing a program whose immediate commercial prospects are uncertain.
The relevant objective is therefore not simply to locate any willing purchaser. A capable steward needs sufficient capital for the next stage of the program, access to the necessary regulatory and technical information, appropriate manufacturing and supply-chain capabilities, the ability to meet remaining clinical or postmarketing requirements, and a credible basis for maintaining the product over time.
Rescue should be understood as a transfer of responsibility, not merely a transfer of title.
Building a Rescue System Before the Next Failure
The existing cases suggest that antibiotic rescue could become more deliberate instead of depending primarily on transactions assembled after a company has already entered severe financial distress.
Achaogen and Nabriva show the breadth of information, relationships, and operational functions that may need to survive a transfer. Iterum adds the constraint of time: discussions with potential counterparties may not be enough if the company cannot remain viable long enough to complete a transaction.
A more formal approach could focus on three areas.
The first is preparation before distress. Developers, particularly those receiving substantial public or philanthropic support, could maintain a transfer-ready continuity package containing the regulatory, clinical, safety, chemistry, manufacturing, and controls information, intellectual property documentation, manufacturing records, and vendor information that a successor would be likely to require. Funding agreements could also consider contingency provisions governing access to supported data and documentation if the recipient ceases operations. Such measures would not assume that failure is inevitable. They would reduce the amount of reconstruction required if a transfer suddenly becomes necessary.
The second is earlier intervention and triage. The Iterum experience suggests a reason to begin evaluating options before liquidation, while the developer can still participate in diligence and transfer activities. A rescue mechanism could assess whether an asset merits preservation based on scientific and clinical evidence, unmet medical need, regulatory status, manufacturing feasibility, completeness of the underlying data package, remaining development requirements, and the prospects for responsible stewardship.
That triage is essential because corporate failure alone does not make an antibiotic worth saving. A rescue system should preserve programs with credible remaining value, not simply prevent every distressed asset from disappearing. The same process could also identify the types of stewards suited to the program, including commercial pharmaceutical companies, specialty anti-infective developers, nonprofit organizations, or other entities capable of assuming the remaining responsibilities.
The third is dedicated financing for the rescue window itself. A limited pool of bridge support could preserve regulatory, safety, manufacturing, and technical functions while diligence proceeds and a successor is identified. Nabriva demonstrates that these transitional costs can be separately recognized and financed within a transaction. A broader mechanism could make comparable continuity support available before a final purchaser has been secured.
Such an approach would not solve the underlying economics that continue to make antibiotic development difficult. It would address a narrower problem that emerges when those economics have already pushed a developer toward failure: how to keep a potentially valuable antibiotic from becoming collateral damage.
Apramycin demonstrates that a program can be recovered after its original developer disappears. Nabriva shows the operational work required to transfer an antibiotic while preserving regulatory, safety, and manufacturing continuity. Iterum shows how financial runway can constrain the opportunity to complete that transfer. These cases provide enough evidence to treat asset preservation as a distinct part of AMR preparedness, with its own timing, financing, and stewardship requirements.
A company’s failure does not have to determine the fate of every antibiotic it leaves behind. Building mechanisms to identify promising stranded assets early, preserve the information and infrastructure surrounding them, finance the transition, and place them with capable new stewards could prevent more viable antibiotic programs from disappearing with the companies that developed them.
