Examiner's Section 2 and Utility Objections to a Diagnostic Claim Set
A Montreal biotech files a Canadian application claiming a method of diagnosing early-stage sepsis by measuring three biomarkers and applying a stated threshold algorithm. The specification reports a study of 40 patients, of which 12 were septic, and states that the method "showed good sensitivity" without giving a number. The examiner issues an action objecting that (i) the claims are directed to a disembodied mental process or a mere discovery of a natural correlation, (ii) the utility is not soundly predicted because the sample is small and no sensitivity or specificity figures are given, and (iii) the claims are broader than the data support because they recite any biological sample and any patient. The applicant has one response left before a final action. The specification as filed contains no additional data, and the applicant does not want to file new matter.
1. Advise on the subject-matter objection, including how to redraft the claims to reduce risk without adding matter.
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The objection conflates two ideas: that the claims recite a mental process, and that they recite a natural correlation. Address each.
Mental process / disembodied step. The claims recite measuring three biomarkers. Measurement is a physical step carried out on a sample using laboratory techniques. That distinguishes the claims from pure calculation or a method of medical treatment by mere instruction. The algorithm is applied to measured data, not to hypothetical data. The strongest drafting move is to tie the measuring step to a specific assay format disclosed in the specification - for example, the immunoassay or the particular platform named in the examples - so the claim recites a concrete physical transformation rather than an abstract comparison.
Natural correlation. The examiner's concern is that the claim covers the discovery that biomarker levels correlate with sepsis. The answer is to ensure the claim requires a specific, practically useful output - a diagnosis of sepsis risk and a treatment or triage step - rather than merely reporting a correlation. If the specification describes a clinical action taken on a positive result, incorporate that step. Do not add a step that is not described; instead, select from the steps the specification already discloses.
Scope narrowing. Restrict "any biological sample" to the sample types actually exemplified (e.g., serum and plasma) and restrict "any patient" to the population studied or to patients presenting with the stated clinical signs. This is a narrowing amendment supported by the specification, so it does not offend the new-matter rule.
Framing for the response. Concede the breadth point, amend, and argue that the amended claims recite a physical measuring step with a concrete diagnostic output. Do not argue that the examiner is simply wrong on all three points; that wastes the response.
2. Address the utility and breadth objections together, given that no new data can be filed.
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Utility in Canada requires that the specification disclose the utility and that the claimed invention work. Where the utility is not demonstrated, it can be soundly predicted if the specification provides a basis for the prediction. The examiner is attacking both limbs: no numbers, and a small study.
What the specification does say. It reports 40 patients, 12 septic, and states "good sensitivity." That is a described utility - diagnosis of early sepsis. The question is whether the prediction is sound.
Arguments available without new data.
- The specification discloses a completed study with a defined cohort, not a bare assertion. A skilled person reading it can see the method was performed and produced a result.
- The number of septic patients (12) is small, but the specification need not report statistical confidence intervals to disclose a utility; it must disclose enough that the skilled person would accept the prediction. Point to any statement in the specification about how patients were selected and how the threshold was derived.
- Utility is assessed as of the filing date and on the basis of the specification plus common general knowledge. Evidence that the biomarkers are known sepsis markers in the literature can support the prediction without adding matter to the specification.
Breadth. The breadth objection is best answered by amendment, not argument. Narrow to the disclosed sample types and patient population. That aligns the claim scope with the data and removes the "any sample, any patient" attack. If the specification describes only one threshold, consider whether the claim should recite the threshold as a range or as the specific algorithm disclosed.
Risk. If the examiner maintains the utility objection after amendment, the applicant faces a final action and then appeal or abandonment. Consider whether a divisional is useful, but note it will face the same specification. Weigh the cost of appeal against the value of the claim set.