Patent: 10,808,037

Summary for Patent: 10,808,037

Title:	Prevention of disulfide bond reduction during recombinant production of polypeptides
Abstract:	Provided herein are methods for preventing the reduction of disulfide bonds during the recombinant production of disulfide-containing polypeptides. In particular, the invention concerns the prevention of disulfide bond reduction during harvesting of disulfide-containing polypeptides, including antibodies, from recombinant host cell cultures.
Inventor(s):	Kao; Yung-Hsiang (San Mateo, CA), Laird; Michael W. (San Ramon, CA), Schmidt; Melody Trexler (Danville, CA), Wong; Rita L. (Redwood City, CA), Hewitt; Daniel P. (Sunnyvale, CA)
Assignee:	Genentech, Inc. (South San Francisco, CA)
Application Number:	16/847,309
Patent Claims:	see list of patent claims

Comprehensive patent-claim and US landscape analysis for U.S. Patent 10,808,037 (HER2 monoclonal antibody produced in CHO cells with pre-harvest air sparging to prevent disulfide reduction)

U.S. Patent 10,808,037 is directed to a process for manufacturing a therapeutic anti-HER2 monoclonal antibody in CHO expression systems, with a defined pre-harvest air-sparging step that maintains dissolved oxygen (dO2) at or above specified thresholds (at least 10% and in dependent claims at least 30%), to inhibit reduction of antibody disulfide bonds during processing. Independent claim 1 frames three essential elements: (i) CHO recombinant expression, (ii) a pre-harvest air-sparging step in the cell culture fluid after a production phase, and (iii) a dosing window tied to dO2 in the pre-harvest fluid (air sparging continues until dO2 is at least 10%). Dependent claims add scale (greater than 5,000 L), air saturation targets (≥30% saturated with air or between 100% saturated to 30% saturated), and explicit antibody scope (trastuzumab). The practical enforcement leverage is concentrated in process conformity: infringement depends on process parameter alignment (sparging timing and continuation and dO2/air saturation thresholds) rather than generic structural properties of the antibody.

What does US 10,808,037 claim about CHO HER2 antibody manufacture with pre-harvest air sparging?

Short answer: The patent claims a manufacturing method that conditions the pre-harvest culture fluid by sparging with air to keep dO2 at or above specific levels, reducing the risk of disulfide bond reduction in the antibody, in CHO cultures producing an anti-HER2 monoclonal antibody. (Claim 1; dependent claims 2-6). Trastuzumab is expressly captured in dependent claim 9.

Claim 1: the infringement-critical feature set

Claim 1 requires all of the following:

1. Method context

   • Producing an antibody by:
   • Expressing the antibody in CHO recombinant host cell culture during a production phase.

2. Process step

   • Sparging the pre-harvest cell culture fluid with air after the production phase.

3. Functional target

   • To inhibit reduction of a disulfide bond in the antibody during processing.

4. Quantitative endpoint

   • Air sparging continues until dissolved oxygen (dO2) in the pre-harvest cell culture fluid is at least 10%.

5. Antibody target

   • Antibody binds human HER2.

Enforcement implication: A process that uses CHO and an anti-HER2 mAb but performs oxygenation only earlier (e.g., in bioreactor feed conditions) without air sparging of the pre-harvest cell culture fluid to the specified dO2 endpoint is unlikely to satisfy claim 1. The patent is not primarily about “a HER2 antibody in CHO,” it is about air sparging of the pre-harvest fluid tied to dO2 thresholds.

Dependent claims: scale and specific oxygen/air saturation bands

Dependent claims increase specificity and narrow the covered parameter ranges:

• Claim 2: same as claim 1, with scale > 5,000 L.
• Claim 3: sparging continued until pre-harvest fluid is at least 30% saturated with air.
• Claim 4: claim 3 plus scale > 5,000 L.
• Claim 5: sparging continued until pre-harvest fluid is between 100% saturated and 30% saturated with air (a banded range).
• Claim 6: dO2 in pre-harvest fluid at least 30%.
• Claims 7-8: include preparing harvested cell culture fluid and recovering/purifying the antibody.
• Claim 9: antibody is trastuzumab.

Enforcement leverage by dependency structure: In litigation, claim 1 sets a broad baseline (≥10% dO2). Dependent claims create additional narrower “hit points.” A manufacturer that chooses lower dO2 and avoids claim 1 could still be exposed if it inadvertently meets the thresholds in operational reality (sensor calibration, mixing uniformity, sparging duration, and the moment at which the “pre-harvest” condition is measured). Conversely, a manufacturer operating above the threshold is more likely to fall into claim 1, making dependent-claim differentiators (scale and saturation bands) less critical.

Which parts of the claims create the strongest infringement risk for generic process change?

Short answer: The dO2 endpoint (≥10% or ≥30%), the requirement that the step involves air sparging of the pre-harvest fluid, and the link to inhibiting disulfide reduction create the most infringement risk. Scale and explicit trastuzumab identity mainly affect dependent claim scope.

dO2 threshold and measurement window

The claim language ties infringement to dO2 in the pre-harvest cell culture fluid meeting a target as sparging continues. That makes infringement sensitive to:

• where/when dO2 is measured (pre-harvest fluid vs. in situ bioreactor DO),
• whether sparging is done with air (not pure oxygen, not N2/oxygen mixes unless they are still “air” within the claim meaning),
• the operational continuity (“continued until”) and the point-in-time compliance.

air sparging vs oxygen-enrichment or agitation

If a process improves oxygenation through gas blending, oxygen enrichment, or headspace aeration only during the production phase, it may still fall outside the claim because claim 1 is explicit about sparging the pre-harvest cell culture fluid. That is a narrower process act than routine aeration.

disulfide bond reduction inhibition

The claim includes a functional purpose: inhibiting reduction of a disulfide bond during processing. Even if a defendant disputes “purpose,” the functional result may still matter if it is intrinsic to the process conditions. Operational evidence typically shows whether higher dissolved oxygen during pre-harvest reduces the redox conditions that promote disulfide reduction.

What patents likely overlap with US 10,808,037 in the CHO HER2 manufacturing space?

Short answer: Without the full patent text, priority/continuation family data, and claim support, the only reliable overlap analysis is at the claim-concept level: patents around (i) oxygen management to prevent mAb disulfide reduction, (ii) CHO manufacturing process controls, and (iii) pre-harvest conditioning steps for maintaining disulfide integrity. The most common overlap areas in this domain are process redox control, oxygen sparging/aeration strategies, and scale-up method claims.

Overlapping technical themes used across patent estates

Across mAb manufacturing patenting, similar themes frequently appear:

• Redox control to preserve disulfide bonds
  • Processes that maintain oxidative conditions or avoid reducing environments during harvest, hold, and early downstream steps.
• Oxygenation strategies
  • Aeration, sparging, dissolved oxygen control, and headspace gas composition to manage DO.
• Pre-harvest/harvest conditioning
  • Adjusting conditions immediately before harvesting to avoid product degradation.
• Scale-up constraints
  • Methods that address mixing, gas-liquid mass transfer, and oxygen gradients in large bioreactors or holding tanks.
• CHO-specific process steps
  • Media and harvest transitions compatible with CHO and monoclonal antibody recovery.

Where overlap is likely strongest

The tightest overlap is likely to come from patents that claim:

• sparging or aerating near harvest or in a harvest hold step, and
• maintaining DO/dO2 above specific thresholds to prevent reduction-related quality attributes (e.g., free thiols, reduced species, disulfide scrambling).

How does US 10,808,037 compare with other process patents for maintaining mAb disulfide integrity?

Short answer: US 10,808,037 is distinguished by its explicit linkage between (i) air sparging of pre-harvest fluid and (ii) quantified dO2 targets. Many other process patents in the space are broader (e.g., generic DO control) or focus on downstream holding/transport rather than a specific “pre-harvest cell culture fluid air sparging to a dO2 endpoint” sequence.

Key differentiators

• Quantified dO2 endpoint: at least 10% in claim 1; at least 30% in claim 6.
• Gas identity and step specificity: sparging with air, not just oxygen control in the bioreactor environment.
• Pre-harvest framing: emphasis on the cell culture fluid “before harvest” rather than generic production-phase DO control.

What does US 10,808,037 cover commercially: trastuzumab and other HER2 antibodies?

Short answer: The patent scope covers anti-HER2 monoclonal antibodies in general in claim 1. Trastuzumab is expressly named in dependent claim 9, which can materially affect commercial coverage if trastuzumab is manufactured using similar CHO oxygenation/pre-harvest sparging conditions.

Trastuzumab-dependent scope

• If a manufacturer produces trastuzumab in CHO and performs pre-harvest air sparging to meet dO2 thresholds, claim 9 provides an additional, easy-to-pin “identification” hook even if broader “HER2 binding antibody” might be litigated on functional characterization.

HER2-binding breadth

• If the process targets other HER2 antibodies (e.g., non-trastuzumab mAbs), claim 1 may still apply if they bind HER2 and meet the process parameters.

When does US 10,808,037 expire and what does that mean for exclusivity or generic risk?

Short answer: Expiration timing cannot be produced from the claim text alone. Without the filing date, priority data, and term adjustments, a precise expiration date cannot be stated here.

Is US 10,808,037 likely to be asserted in Paragraph IV-style generic entry or in biosimilar contexts?

Short answer: Given the patent is a process claim for manufacturing an antibody in CHO cells with a specific pre-harvest oxygenation step, the most direct enforcement context is against products that use that process or a substantially similar process. The filing framework depends on whether the challenged product is a small-molecule (unlikely here) or a biologic. For trastuzumab biosimilars, the relevant enforcement pathway is typically biosimilar litigation, not Orange Book Paragraph IV.

Process-claim infringement model

• A biosimilar manufacturer that performs comparable CHO expression and pre-harvest air sparging to meet the dO2 endpoint may face process infringement allegations.
• A manufacturer that avoids meeting the dO2 threshold or does oxygenation only during production may reduce risk.

What does an Orange Book status check imply for US 10,808,037?

Short answer: Orange Book listing status depends on the specific drug product associated with the patent and the patent’s listing in FDA systems. That requires dataset retrieval that cannot be derived from claim text alone.

How strong are US 10,808,037 claims against design-around (oxygen management and sparging changes)?

Short answer: The claims provide clear design-around levers: operate below the dO2 threshold in the pre-harvest fluid; change the gas identity so it is not “air”; avoid sparging the pre-harvest fluid; or move the oxygenation step earlier so the pre-harvest fluid does not meet the claimed endpoint.

Most realistic design-arounds

• Avoid dO2 ≥10% at pre-harvest: set a lower oxygenation endpoint in the pre-harvest fluid.
• Alter the physical step: replace sparging with another conditioning mechanism (e.g., agitation without gas sparging, or oxygen-enriched systems that do not constitute “air”).
• Change the step location in the process: do not sparge pre-harvest fluid; perform conditioning only during production phase where claim 1’s “pre-harvest cell culture fluid” requirement may not be met.

Why design-around can be brittle

Even if a process aims to comply operationally, actual manufacturing can create transient regions where dO2 rises above a threshold during hold/transfer. Claim construction typically treats “continued until” as including operational determination of compliance. If sensors show compliance with dO2 thresholds, defendants may struggle to prove non-infringement.

What claims in US 10,808,037 are most vulnerable to validity attacks?

Short answer: Vulnerability depends on the patent’s full specification, the scope of the support for the quantitative oxygen thresholds, and prior art at the effective filing date. That cannot be assessed from the claim list alone.

Common validity pressure points in this category

Where oxygen-sparing or pre-harvest conditioning is claimed with quantified endpoints, typical validity issues include:

• Obviousness: whether similar air sparging or oxygenation/redox control steps with comparable endpoints were known for mAb quality attributes like reduced disulfides.
• Enablement and written description: whether the specification supports the full range of claimed thresholds (≥10%, ≥30%, and saturation bands) and how to reproduce the results across scales.
• Definiteness: whether “dO.sub.2 in the pre-harvest cell culture fluid” and “% saturated with air” are clearly defined relative to measurement method and reference conditions.

Key takeaways

• US 10,808,037 is a process patent focused on pre-harvest air sparging of CHO culture fluid to maintain dO2 at or above defined thresholds, aiming to prevent disulfide bond reduction in an anti-HER2 therapeutic mAb.
• Claim 1 is the core infringement anchor: CHO expression + pre-harvest air sparging + disulfide reduction inhibition + dO2 ≥10%.
• Claims 3-6 tighten oxygenation to ≥30% air saturation or dO2 ≥30%, creating high-stakes exposure if manufacturing targets high oxygen during pre-harvest holds.
• Claim 2/4 adds a scale filter (>5,000 L), which may matter if oxygenation is only engineered for smaller vessels.
• Claim 9 expressly names trastuzumab, increasing the commercial relevance for CHO-based trastuzumab manufacturing processes.
• Design-around is most plausible by avoiding the dO2 threshold at pre-harvest, changing the gas step away from “air,” and/or moving oxygenation earlier in the process so the pre-harvest fluid does not meet the endpoint.

FAQs

1. How can a manufacturer prove non-infringement of US 10,808,037 when using DO control during the production phase?
2. What process parameters besides dO2 can drive disulfide reduction risk in CHO harvest holds and how do they affect patent exposure?
3. Do air saturation percentage and dissolved oxygen percentage correlate consistently across bioreactor and harvest-tank configurations?
4. What litigation strategy is typical for asserting process patents against biosimilar manufacturers producing trastuzumab-like HER2 antibodies?
5. How does changing bioreactor scale or harvest hold duration impact the likelihood that pre-harvest fluid meets dO2 thresholds?

References

1. U.S. Patent 10,808,037 (claims provided in prompt).

Details for Patent 10,808,037

Applicant	Tradename	Biologic Ingredient	Dosage Form	BLA	Approval Date	Patent No.	Expiredate
Genentech, Inc.	HERCEPTIN	trastuzumab	For Injection	103792	September 25, 1998		2040-04-13
Genentech, Inc.	HERCEPTIN	trastuzumab	For Injection	103792	February 10, 2017		2040-04-13