Appendix 25

• Author: Kenneth Dorsney
• Pages: 683-715

683

EXP ER T DE CL AR AT IO N IN SU PP OR T OF CL AI M CO NS TR UC TI ON

IN THE UNITED STATES DISTRICT COURT

[Name of District]

[DISTRICT COURT CAPTION]

DECLARATION OF [NAME OF EXPERT] REGARDING

CLAIM CONSTRUCTION OF U.S. PATTENT NO. 1

[Insert Table of Contents]

[Insert Table of Exhibits]

I, [Name], submit this declaration in the above-captioned matter on behalf of

Defendant3 in connection with the construction of the claim term "gelling agent" in the

claims of United States Patent number 1 (the "‘001 Patent").

I. Summary of Opinions

1. The term "gelling agent" in the claims of the ‘001 Patent would be

construed by a person of ordinary skill in the art in [Date] to mean or refer to an excipient

(or substance) that, when in contact with water, hydrates and swells to form and maintain

a gel barrier layer over the surface of the dosage unit, which imparts sustained release of

the active ingredient.

2. The relevant art for the ‘001 Patent is formulation of sustained release solid

oral dosage forms. Based on the specification of the ‘001 Patent as a whole, and various

statements therein, a person of ordinary skill in the art would understand all of the

claimed inventions to be directed to sustained release solid oral dosage forms,

particularly tablets and capsules.

3. A person of ordinary skill in that art in [Date]: (a) would have had at least a

bachelor degree in pharmacy or a related field, plus several years of experience in

formulating pharmaceutical products including solid oral dosage forms; or (b) would

have had an advanced degree (Masters or Ph.D.) in pharmacy or a related field, with

concomitantly fewer years of experience in formulating pharmaceutical products

including solid oral dosage forms.

4. Such a person would have been familiar with the terminology and

technology of the five principal sustained release systems known and used in the art by

[Date]. He also would have known that the terms "gelling agent" and "gel" were used to

refer to the conventional gel-forming sustained release system, which was one of the two

most widely-used systems used in sustained release solid oral formulations.

5. Specifically, such a person would have recognized the term "gelling agent"

to refer to the component in the gel-forming system that hydrates and swells to form and

maintain a gelatinous barrier layer over the surface of the tablet, most commonly referred

to as a "gel layer" or "gel" around the tablet. Thus, "gel layer" was the system-defining

feature. It was responsible for controlling release of the drug by serving as a barrier to

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gastric fluid penetration of the dry tablet core, and providing a diffusion path that could

be controlled by, among other things, varying the amount and physicochemical properties

of the "gelling agent."

6. He also would know that the rapid formation and maintenance of this gel

layer over the entire tablet surface is the system-defining mechanism of sustained release.

He would know that the "gelling agent" must be present in sufficient amount and have

physicochemical qualities necessary to quickly form and maintain this layer over the

surface of the tablet. Otherwise, aqueous gastrointestinal fluids would penetrate the tablet

core, leading to the rapid disintegration of the tablet, and so-called "immediate release" or

potential "dose dumping" of the drug.

7. A person of ordinary skill in the art would have seen from the

specification and claims of the ‘001 Patent that the inventors were using the term "gelling

agent" in this industry-standard sense, as used and understood in the art to refer to the

well-known gel-forming excipient in the gel-forming sustained release system. The

claimed use of HPMC in various combinations, viscosities and concentrations was well-

known in the art to refer specifically to the gel-forming excipient in this sustained release

system. The specification expressly incorporates the prior known use of "gelling agents,"

in its description of "gelling agent" and reflects the meaning of this known art. Within the

gel-forming sustained release system, a "gelling agent" is "a substance, particularly a

hydrophilic substance, which forms a gel when in contact with water." And the examples

of "gelling agents" listed thereafter were all known in the art to have been used, either

alone or in combination, as the bases of gel-forming systems.

8. Finally, I disagree with Plaintiff’s proposed construction of the term

"gelling agent" to mean "one or more substances that (a) when in contact with water form

a semisolid system enclosing and interpenetrated by water and (b) are present in

sufficient amounts within the formulation to provide release of the active pharmaceutical

ingredient over an extended period of time." While the use of mixtures of particular

gelling agents were known in the art, this construction appears to suggest a meaning well

outside the context of the "gel" or "gel layer" system known in the art of sustained release

solid dosage oral forms. The evidence cited by Plaintiff (texts, patents and dictionaries)

comes from contexts other than sustained release solid oral dosage forms, and thus does

not reflect how a person ordinary skill in the art would understand the term "gelling

agent" in the ‘001 Patent.

9. Specifically, Plaintiff’s construction would appear to contemplate any

interaction with water that forms or leaves behind an arguably semi-solid structure of any

type, size or amount—and in any location. The same hydrophilic excipients that can be

used (typically in high concentrations) to form the gel layer in a gel-forming system are

used (typically in lower concentrations) in non-gel-forming systems for other purposes

without forming the gel layer—even in sustained release formulations based on inert or

erodible matrix systems. Under Plaintiff’s construction of "gelling agent," however, the

claims of the ‘001 Patent might be argued to apply on their face to any sustained release

formulation in which a hydrophilic excipient is used, without regard to whether it forms

the system-defining gel layer. This is inconsistent with how a person of ordinary skill in

the art at the time would have understood the term "gelling agent" in the ‘001 Patent, in

light of the intrinsic evidence of the specification indicating that the invention is not the

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discovery of a new sustained release system or new "gelling agent," but rather a way to

use the known gel-forming system with the particular drug, [active ingredient].

II. Educational and Professional Background

10. Presently, I am _____ at _____, a position I have held since [Date]. For

the last __ years, I have been teaching both undergraduate and graduate courses in

applied biopharmaceutics, pharmaceutical dosage forms, modified release products, and

pharmaceutical manufacturing. I have supervised more than __ graduate students and a

number of postdoctoral fellows and visiting scientists working in the area of drug

delivery systems.

11. I earned my B.S. degree in Pharmacy from _____, in [Date] and earned

my Ph.D. in pharmaceutics from _____ in [Date].

12. My research includes the disciplines of biopharmaceutics and

pharmaceutical dosage form development. This research involves the study and

evaluation of active pharmaceutical ingredients ("APIs" or "drugs"), pharmaceutical

compositions and delivery systems employed for delivering the API to a particular site in

a patient where the drug is released or needed. This research encompasses the principal

aspects of pharmaceutical compositions: from the initial concepts or pre-formulation

work through industrial scale production of the final pharmaceutical composition. This

research also includes the study and evaluation of the manner in which the drug and

pharmaceutical composition behave or react in the patient.

13. I have attained the status of Fellow of the American Association of

Pharmaceutical Scientists ("AAPS") for the Advancement of Science. I also have been

_____ as well as a member of numerous pharmaceutical societies including _____

14. Over the last __ years, I have authored or co-authored more than __

articles, many book chapters, and have published more than __ abstracts. Many of these

publications relate to the design, development, and testing of pharmaceutical

compositions employing various drug delivery technologies. I have been invited to

present seminars at_____. In addition, I have presented many lectures, seminars and

research papers to various pharmaceutical associations worldwide.

15. I have been retained to consult with approximately __ pharmaceutical

companies. My work with these companies includes providing expertise in areas such as

biopharmaceutics (bioavailability and bioequivalence requirements), formulation

development issues, trends in modified release pharmaceutical compositions, and factors

involved in the development of pharmaceutical compositions.

16. I have received a number of awards, including _____.

17. I have been awarded __ United States Patents for pharmaceutical

compositions and devices related to modified release technology.

18. Further details of my educational and professional qualifications appear in

my curriculum vitae, attached hereto as Exhibit _.