by Chris Holman
ImmunoGen, Inc. v. Hirshfeld, 2022 WL 885774, (Fed. Cir. Mar. 25, 2022) (nonprecedential)
The patent application at issue in this case claims a method of treating a cancer patient by administering mirvetuximab (an immunoconjugate drug) “at a dose of 6 milligrams (mg) per kilogram (kg) of adjusted ideal body weight (AIBW) of the patient.” The purported invention arose out of the discovery that administration of mirvetuximab at the recited dosage significantly reduces the severe ocular side effects that were observed during Phase 1 clinical trials when the drug was administered at a dose of 7 mg per kg of the patient’s total body weight (“TBW”). After the Patent Trial and Appeal Board (“Board”) affirmed the examiner’s rejection of the pending claims for obviousness and obviousness-type double patenting, the applicant (ImmunoGen) filed a § 145 suit in the Eastern District of Virginia challenging the rejections. The district court determined on summary judgment that the claims are “fatally indefinite and fatally obvious” as a matter of law. On appeal, the Federal Circuit vacated the grant of summary judgment and remanded for further proceedings.
The district court’s indefiniteness ruling was based on the claims’ recitation of “AIBW,” a term which the court found was not defined in the application in manner that would inform a skilled artisan, with reasonable certainty, as to the scope of the invention (the Nautilus standard). The application defines AIBW as “a size descriptor that accounts for sex, total body weight, and height.” It further defines ideal body weight (“IBW”), which is used to calculate AIBW, as “an estimate of weight corrected for sex and height, and optionally frame size.” The AIBW and IBW definitions each includes a specific formula, introduced by the phrase “for example,” for calculating the respective values.
The formulas are reproduced below in the form of equations:
AIBW = IBW + 0.4(Actual weight in kg – IBW)
IBW (male) = 0.9(Height in centimeters) – 88
IBW (female) = 0.9(Height in centimeters) – 92
These “example” formulas were also reproduced in Example 4 of the application, which relates to the dosing of mirvetuximab.
In support of its decision finding the claims indefinite, the district court relied primarily on the fact that the definitions section of the application preceded the AIBW formula with the language “for example,” which the court found “ma[de] clear that there are multiple ways to calculate AIBW,” thereby “leav[ing] a skilled artisan to wonder or to guess whether the formula provided is the only one covered by the ’809 Application.” This uncertainty was, in the view of the district court, compounded by: (1) similar “for example” language accompanying the IBW formula; (2) the disclosure that IBW corrects “for sex and height, and optionally frame size”; and the incorporation by reference in its entirety of “Green,” an article that discloses several methods for calculating IBW and lists correction factors, each specific to a different drug, that can be used to adjust IBW to AIBW.
On appeal, the Federal Circuit found that the material factual findings underlying the district court’s definiteness ruling were far from undisputed. In particular, ImmunoGen had identified other intrinsic evidence a skilled artisan would consider in determining the scope of the claims, including that: (1) the claims and specification are drawn to a specific dosing regimen for a specific immunoconjugate, which is significant in light of expert testimony that the correction factor used to calculate AIBW is drug-specific; (2) Example 4 describes dosing mirvetuximab in accordance with the claimed method and uses the same AIBW and IBW formulas disclosed in the definitions section; and (3) during the prosecution of the ’809 Application, the USPTO never disputed the definiteness, or gave any indication it failed to understand the meaning, of the now-allegedly indefinite term. ImmunoGen also presented extrinsic evidence regarding the knowledge of a skilled artisan. For instance, both parties’ experts testified that AIBW dosing involves drug-specific formulas and correction factors.
The Federal Circuit also found that the district court had erred in concluding that there was no disputed question of material fact with respect to obviousness. It was undisputed that AIBW dosing had not previously been used for mirvetuximab, or for that matter any other immunoconjugate drug.
If on remand the court ultimately finds the claims indefinite for defining a critical claim limitation in terms of an “example,” it would not be the first time that the Federal Circuit has flagged this as an issue. In Interval Licensing LLC v. AOL, Inc., 766 F.3d 1364 (Fed. Cir. 2014), the Federal Circuit held claims invalid for indefiniteness because the specification failed to adequately define the claim limitation “unobtrusive manner that does not distract a user.” While “recognizing that a patent which defines a claim phrase through examples may satisfy the definiteness requirement,” the court “decline[d] to cull out a single “e.g.” phrase from a lengthy written description to serve as the exclusive definition of a facially subjective claim term.” The court observed that “[h]ad the phrase been cast as a definition instead of as an example—if the phrase had been preceded by “i.e.” instead of “e.g.”—then it would help provide the clarity that the specification lacks.”
Still, I think that Interval Licensing can be readily distinguished over ImmunoGen, in that Interval Licensing’s “unobtrusive manner that does not distract the user” claim limitation seems much more “facially subjective” than ImmunoGen’s “adjusted ideal body weight.”
A brief Finnegan firm educational observation today re another recent Fed. Cir. reversal of a D.C. claim interpretation also seems relevant here: “At the top of the evidentiary hierarchy that is used during claim construction is the language of the claims and the support found in the specification. “[A] court may not read into a claim a limitation from a preferred embodiment, if that limitation is not present in the claim itself.” Bayer AG v. Biovail Corp., 279 F.3d 1340, 1348 (Fed. Cir. 2002). Of course, the practitioner should also be cautioned that the above claim construction principle has limits: “unless that embodiment is in fact the entire invention presented.” Vulcan Eng’g Co. v. Fata Aluminum, Inc., 278 F.3d 1366 (Fed. Cir. 2002). And remember, from Phillips v. AWH Corp., 415 F.3d 1303 (Fed. Cir. 2005) (en banc), the specification is the single best guide to construing a claim.” [But of course these 3 not exactly consistent Fed. Cir. quotations per se need to be read in their case contexts and other statements in the same decisions.]
I’m not sure how it squares that both parties’ experts testified that AIBW dosing involves drug-specific formulas and correction factors while at the same time it was undisputed that AIBW dosing had not previously been used for mirvetuximab, or for that matter any other immunoconjugate drug
So how would PHOSITA extrinsically know how to dose mirvetuximab if AIBW had not been used for any prior immunoconjugate drug?
It also seems slightly janky that a 14% dose increment would seriously decrease a side effect while the dose/body mass calculation is apparently (by the language of the patent) somewhat flexible…
PS It’s not Russian patents of mass destruction that should be keeping anyone up at night….
“also seems slightly janky that a 14% dose increment would seriously decrease a side effect while the dose/body mass calculation is apparently (by the language of the patent) somewhat flexible…”
That’s the needle that the patentee is trying to thread here and it’s not easy, especially if you shot yourself in the foot by not defining terms well. Administering a lower dosage to reduce side effects is not exactly a new concept. It’s a bit unclear why it should matter how the very slightly lower dosage is calculated (especially if I’m doing the math in my brain and/or using prior art data, e.g., a drug metabolite level, to make the determination) but that’s another issue …
“how would PHOSITA extrinsically know how to dose mirvetuximab if AIBW had not been used for any prior immunoconjugate drug”
The eye of the needle again. The patentee would argue that the skilled artisan would read the patent and resolve all the ambiguity in the manner the patentee intended (i.e., in the manner which yields both the desired result and a valid patent).
Threading needles is what district courts do. But why bother? They have all the value of a pre-season NFL game, even after jury verdicts.
The CAFC should just be expanded to hear all the cases denovo, and would be appellants would just have to be lucky duckies to gain cert after that…or maybe the DC Circuit for the occasional (or not so occasional for the CAFC ) non-patent related errors of law….
“ It was undisputed that AIBW dosing had not previously been used for mirvetuximab, or for that matter any other immunoconjugate drug.”
Respectfully, who cares? The point here is that applicants want to claim to an allegedly non-obvious dosage regimen for an existing drug which was known to have undesirable side effects at too high of a dosage.
And then the applicants couldn’t be bothered to define this allegedly non-obvious dosage regimen clearly. We can speculate as to what caused that failure but it was a failure, and a spectacular one at that.
Also what difference does it make if the Examiner didn’t flag the indefiniteness issue? Regardless of the ultimate resolution, the issue is there. The facts show that there IS ambiguity in the dosage formula. It should have been caught during Exsmination (or during drafting).
What difference does it make…?
Seriously?
Let’s put it this way: let’s say the Examiner finds nothing wrong with the application and you get a first action allowance. Is that a better patent as a result? Should courts treat it that way?
In this case, the patent is granted and the reward is that you get to assert it in court and the burden is on the other side to demonstrate invalidity. By itself, the mere fact that the Examiner didn’t find a problem with X adds squat to the “strength” of the patent and that’s as it should be.
Your follow-up question belies the inanity of your first post.
Think about it.
“ Your follow-up question belies the”
*click*
MM might enjoy this latest news of a multicultural and multiracial female identifying individual suing for discrimination and failure of others to recognize her true nobility, or sorry, multiculturalism.
link to yahoo.com
She was deemed as “presenting as white,” therefore — for equity’s sake — she must be an oppressor, and any recrimination from her must solely be a product of white fragility (or white guilt).
(because those leveling such charges enjoy an Activist Privilege, and cannot be wrong)
anon, unfortunately, that is the way people think now.
Let me correct you:
That SOME people think now.
Make no mistake – the PC nanny state that you refer to as “the people” is nothing more than a power grab of the identity politics of Neo-Liberalism.
This is related to IP law…how?
It’s not.
At all.
It’s yet another installment of 6’s faux “liberalism” being used to taunt the very Liberal Malcolm.
IP law, as is all fields these days are intimately related to and in need of multicultural candidates of course!
6, that is a fittingly bizarro “answer.”
You still trying to front the “equity” mantra?
Aw, so cute.
Lol – the return of the mindless *click*
How special.
I tend to agree with MM here although I understand what anon in his fantasy examination regime is meaning as well.
This has nothing to do with “fantasy examination regime,” 6.
Malcolm’s inanity is in his blanket “who cares” approach.
As to:
‘Still, I think that Interval Licensing can be readily distinguished over ImmunoGen, in that Interval Licensing’s “unobtrusive manner that does not distract the user” claim limitation seems much more “facially subjective” than ImmunoGen’s “adjusted ideal body weight.”’
Maybe it’s a good thing that the legal fiction known as PHOSITA is not “distracted” by notions (read that as feelings, or sniffs) of “facially.”
Cognitive processing (the arena of distractions) is as real and scientific as body weight processing, so the imputed subjectivity that one area of innovation is more deserving (and thus should have such terms considered more definitive) should be quashed.
The point is that the use of subjective descriptors (“pleasing”; “non-distracting”) in patent claims is strongly disfavored as compared to the use of objective descriptors (“between 1 and 5 kilograms”).
Nothing controversial or remotely difficult about this concept. Feel free to lean the hard way.
… and you completely miss my point.
Maybe it was the less-than-objective “ideal” that you also missed.
I would have just claimed:
“wherein the drug is administered at a dose effective to achieve favorable effects while reducing unfavorable effects.”
Just leave it at that. that should be valid according to the commentariat here
“ that should be valid according to the commentariat here”
If you completely lack reading comprehension skills and you have an ax to grind, I suppose you might think that but you’d be wrong.
The context here is that this a known drug and the patent applicants are trying to navigate through the prior art by asserting an “improved” dosage. It’s one thing to get application like that past the PTO and a whole other thing to assert it in court against a super invested and knowledgable defendant.
You need good data and solid definitions in your application. Good lawyers help but they won’t save you if the fundamentals are weak.
OT, but…
link to ipwatchdog.com
Nice.
From the link:
“The overarching sentiment from panelists was that all three branches of U.S. government are failing to prioritize a strong IP system, which could result in the United States falling behind as an innovation leader, to the benefit of potential bad-faith competitors like China and Russia.”
Panelists are worried about Russia (lol) “benefitting” because (trying not to laugh here) we don’t grant enough patents and make them easier to enforce and harder to invalidate?
Stay away from the hard drugs, folks.
Yeah its totally russia that will like totally benefit and stuff.
… because it’s not just like Russia just dumped all of their agreed upon IP treaty obligations or anything like that….
Oh wait, it is exactly like that.
Which is going to help them how exactly? Worst case. Especially focusing on short term (after the war everyone will go back to more or less ignoring them/using them for a red scare punching bag for clicks).
“Which is going to help them how exactly?”
While this is an interesting question, it is NOT on point to the immediate discussion.
We can discuss this, but I want you to recognize that your question is a tangent – let’s see you respond first to the point at hand.
No, not really. Because I don’t even know what alternate “point” you could be discussing other than perhaps “The overarching sentiment from panelists was that all three branches of U.S. government are failing to prioritize a strong IP system”. Which I mean, I have nothing all that much to say regarding. They might be right. They might be wrong. I personally think the PTO is chugging along quite nicely protecting IP, and the courts appear to be doing the same. The legislature dilly dallies and kicks the can as usual. Maybe that is too little for the other guys. I’m only interested in the russia angle.
“Which I mean, I have nothing all that much to say regarding….
I’m only interested in the russia angle.”
Ok – so what exactly do you think IS “the Russia angle?”
No bites, 6…?
Are you doubting that there are bad faith actors, or are you doubting that Russia and China would be considered examples of bad faith actors?
… and of course, we will NOT have Malcolm actually engage in a conversation – more of his well-trod script of drive-by screed.
Were there no original dependent claims spelling out specific “adjusted ideal body weight” formulas?
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