DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 9/17/26 has been entered.
Claims 29-31, 33-39, 45, 61, and 63-67 are pending.
Claims 29, 30, 33, 45, 61, and 67 have been amended by Applicant.
Claims 29-31, 33-39, 45, 61, and 63-67 are currently under consideration.
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
This Office Action contains New Rejections.
Rejections Withdrawn
All previous rejections are withdrawn.
New Rejections
Claim Rejections - 35 USC § 112
Claims 29-31, 33-39, 45, 61, and 63-67 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Claims 29-31, 33-39, 45, 61, and 63-67 are rejected because claims 29, 45, and 61 each recite: “…comparing the ratio of the long heavy chain to the short heavy chain and….” There is insufficient antecedent basis for “the ratio of the long heavy chain to the short heavy chain” in the claims.
Claim Rejections - 35 USC § 103
Claim(s) 29-31, 33-39, and 45 is/are rejected under 35 U.S.C. 103 as being unpatentable over Gomez et al (Biotechnology and Bioengineering, 2018, 115(12): 2930-2940; 9/28/23 IDS) in view of Mchugh et al (Biotechnology Progress, 2020, 36(e2959): 1-11), Torres et al (PLOSOne, 2018, 13(3)(e0194510): 1-23), Ali et al (WO 2019/140196 A1; 7/18/2019; 9/28/23 IDS), Schlatter et al (Biotechnol Progress, 2005, 21: 122-133), Joshi et al (MARS, 2019, 11(7): 1254-1265), Dillon et al (MARS, 2017, 9(2): 213-230), and Yin et al (MARS, 2016, 8(8): 1467-1476)).
Gomez et al teaches a biphasic cell culture process for generating asymmetric multispecific antibodies comprising a “temperature shift” cell culture temperature regime that comprises culturing stably transformed clonally derived CHO host cells (“cell line X”) expressing the asymmetric multispecific antibody in a vessel comprising a standard culture medium at 36 °C to maximize cell growth first for 3 days and then shifting to culturing the cells at 32.5 °C, and harvesting of the asymmetric multispecific antibody product on days 3, 6, 8, 10, and 13 for analysis, followed by protein-A or CEX chromatography purification of the asymmetric multispecific antibody (see 2.1 Cell culture at right column on page 2931, in particular). Gomez et al further teaches the biphasic cell culture process for generating asymmetric multispecific antibodies comprising a “temperature shift” cell culture temperature regime with the clonally derived CHO host cells (“cell line X”) expressing the asymmetric multispecific antibody as an “optimal process” that led to higher yield and “improve quality” (see Table 4, and left column on page 2939, in particular). Table 4 of Gomez et al further illustrate that the clonally derived CHO host cells (“cell line X”) expressing the asymmetric multispecific antibody cultured with the “temperature shift” temperature regimen and purified with protein-A resulted in higher yields and strikingly reduced expression of both “Half B-Ab” impurity (comprising an unpaired heavy chain) and LMW impurity as compared to clonally derived CHO host cells (“cell line X”) expressing the asymmetric multispecific antibody cultured at a constant temperature regimen and purified with protein-A (see Table 4 and Figure 4 for description of “Half B-Ab”, in particular).
While the clonally derived CHO host cells (“cell line X”) expressing the asymmetric multispecific antibody cultured with the “temperature shift” temperature regimen purified with protein-A or CEX resulted in similar “HMW” impurities (comprising a mis-paired long heavy chain) as compared to clonally derived CHO host cells (“cell line X”) expressing the asymmetric multispecific antibody cultured at a constant temperature regimen and purified with protein-A or CEX, Gomez does teach a slightly higher level of the HMW impurity with the constant temperature regimen than the temperature shift regimen purified with protein-A as compared to the cells cultured at a constant temperature regime and purified by protein-A (see Table 4 and pages 2936-2937 for description of “HMW”, in particular). See Figure 4:
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Gomez et al further teaches effects of temperature regimes on other clonally derived CHO host cells expressing the same asymmetric multispecific antibody as “cell line X” did not mirror those exhibited by “cell line X” (page 2938, in particular).
Gomez et al does not explicitly teach comparing ratios of lung heavy chains to short heavy chains or recited “selecting” steps or generating an asymmetric multispecific antibody comprising an IL-21 mutein. However, these deficiencies are made up in the teachings of Mchugh et al, Torres et al, Ali et al, Schlatter et al, Joshi et al, Dillon et al, and Yin et al.
Mchugh et al teaches temperature shifts to lower culture temperatures are frequently employed in manufacturing of protein therapeutics in mammalian cells to improve productivity, viability, and quality attributes that the extent to which a temperature shift affects productivity and quality may vary depending on the expression host and characteristics of the expressed protein (Abstract, in particular). Mchugh et al further teaches two CHO clones expressing different monoclonal antibodies respond differently to a temperature shift despite having a parental CHO cell line (Abstract, in particular).
Tores et al teaches two clonally derived CHO cell lines (CN1 and CN2) that recombinantly express the same antibody (anti-TNFa) differ from one another, in viability and antibody production, when clonally derived CHO cell lines are cultured at different temperatures (Fig. 1, in particular). A lower temperature seemed to increase antibody production and anti-TNFa mRNA expression to a greater extent in the CN2 clone, as compared to the CN1 clone (Fig. 1 and Fig. 3, in particular).
Ali et al teaches an asymmetric multispecific antibody comprising a PD-1 targeting antibody fused to an IL-21 mutein that overcomes significant barriers associated with cytokine therapeutics and allows for antibody-like dosing and selectively delivery of the IL-21 mutein in a PD-1 targeted manner wherein the IL-21 mutein can selectively activate and expand PD-1 expressing T cells in vivo ([0089], in particular). The asymmetric multispecific antibody of Ali et al has the following general structure:
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As illustrated above, the multispecific antibody of Ali et al comprises four amino acid chains: two light chains, a long heavy chain, and a short heavy chain. The prior art teaches optimizing ratios of levels of polypeptide chains of multi-polypeptide constructs generated in recombinant cells used to generate the multi-polypeptide constructs (Abstract of Schlatter et al; paragraph spanning columns on page 1263 of Joshi et al; page 218 of Dillon et al; right column on page 1471 of Yin et al).
One of ordinary skill in the art would have been motivated, with a reasonable expectation of success, to perform a combined method of identifying a clonal cell line that can optimally generate the asymmetric multispecific multi-polypeptide antibody construct comprising a long heavy chain a short heavy chain, such as that of Ali et al, under optimized culture conditions comprising (i) establishing numerous clonally derived cell lines expressing the asymmetric multispecific multi-polypeptide antibody construct wherein the polypeptide chains of the cell lines express different amounts of each polypeptide (including those that differ in ratios of long heavy chain : short heavy chain of the construct), (ii) culturing at least one cell culture of each clonally derived cell lines at a first temperature (temperature-shift) regime at 36 °C for three days and then shifting the culture temperature to 32.5 °C and analyzing the antibody product on days 3, 6, 8, 10, and 13 (as taught by Gomez et al), (iii) culturing one other cell culture of each clonally derived cell lines continuously at a temperature regime of 36 °C (continuous temperature regime of Gomez et al), (iv) purifying the expression products by chromatography and comparing the (a) ratios of each chain the construct generated by each cell line to one another and (b) the expression of product-related asymmetric antibody production impurities of Gomez et al (including unpaired or mis-paired long heavy chains) for each clonally derived cell lines at each temperature regimen, and (v) selecting a clonally derived cell line that exhibits culture condition(s) that result in optimal asymmetric multispecific antibody production with reduced expression of product-related impurities of unpaired or mis-paired long heavy chains (as taught by Gomez et al) and then culturing the selected clonally derived cell line (which may or may not be a cell line with a lower ratio of long heavy chain to short heavy chain) in the culture condition(s) that result in optimal asymmetric multispecific antibody production for the selected clonally derived cell line in an effort to (i) optimize generation of the asymmetric multispecific multi-polypeptide antibody construct and (ii) identify temperatures and ratios that correlate with optimized generation of the asymmetric multispecific multi-polypeptide antibody construct because (i) Mchugh et al teaches temperature shifts to lower culture temperatures are frequently employed in manufacturing of protein therapeutics in mammalian cells to improve productivity, viability, and quality attributes that the extent to which a temperature shift affects productivity and quality may vary depending on the expression host and characteristics of the expressed protein and (ii) multispecific antibody of Ali et al comprises four amino acid chains and the prior art of Schlatter et al, Joshi et al, Dillon et al, and Yin et al all teach optimizing ratios of levels of polypeptide chains of multi-polypeptide constructs generated in recombinant cells used to generate the multi-polypeptide constructs. Further, the combined method evaluates multiple clonally derived cell lines with each temperature regimen because Mchugh et al teaches temperature shifts to lower culture temperatures are frequently employed in manufacturing of protein therapeutics in mammalian cells to improve productivity, viability, and quality attributes that the extent to which a temperature shift affects productivity and quality may vary depending on the expression host and characteristics of the expressed protein (Abstract, in particular), Tores et al teaches two clonally derived CHO cell lines (CN1 and CN2) that recombinantly express the same antibody (anti-TNFa) differ from one another (sometimes slightly), in viability and antibody production, when clonally derived CHO cell lines are cultured at different temperatures (Fig. 1, in particular), and Gomez et al teaches effects of temperature regimes on other clonally derived CHO host cells expressing the same asymmetric multispecific antibody as “cell line X” did not mirror those exhibited by “cell line X” (page 2938, in particular).
Further, it is predictable that selected clonally derived cell lines of embodiments of the combined method include those that exhibit a culture condition that results in optimal asymmetric multispecific antibody production that may exhibit strikingly reduced expression of one product-related impurities of unpaired or mis-paired long heavy chains under said culture condition (such as temperature shift regime), but may have a bit higher level of a different product-related impurity at other conditions (such as continuous temperature regime), as exhibited by “cell line X” of Gomez et al.
Further, one of ordinary skill in the art would have been motivated, with a reasonable expectation of success, to perform said combined method wherein the selected clonally derived cell line that exhibits a culture condition that results in optimal asymmetric multispecific antibody production with reduced expression of product-related impurities of unpaired or mis-paired long heavy chains is inoculated into a bioreactor (such as a bioreactor comprising a shake flask of page 2931 of Gomez et al), culture the selected clonally derived cell line under said culture condition that results in optimal asymmetric multispecific antibody production, and harvest and chomotographically purify the multispecific antibody (as taught by Gomez et al) in order to obtain a purified the PD-1 targeting antibody of Ali et al fused to an IL-21 mutein that overcomes significant barriers associated with cytokine therapeutics and allows for antibody-like dosing and selectively delivery of the IL-21 mutein in a PD-1 targeted manner wherein the IL-21 mutein can selectively activate and expand PD-1 expressing T cells in vivo ([0089] of Ali et al, in particular)
This is an example of use of known techniques (optimization by temperature-shifts and expression ratios of multi-polypeptide constructs) to improve similar methods or products in the same way. This is further an example of some teaching, suggestion, or motivation in the prior art that would have led one of ordinary skill to modify the prior art reference or to combine prior art reference teachings to arrive at the claimed invention. Therefore, the invention as a whole would have been prima facie obvious to one of ordinary skill in the art, absent unexpected results.
Claim Rejections - 35 USC § 103
Claim(s) 29-31, 33-39, 45, 61, and 63-67 is/are rejected under 35 U.S.C. 103 as being unpatentable over Gomez et al (Biotechnology and Bioengineering, 2018, 115(12): 2930-2940; 9/28/23 IDS) in view of Mchugh et al (Biotechnology Progress, 2020, 36(e2959): 1-11), Torres et al (PLOSOne, 2018, 13(3)(e0194510): 1-23), Ali et al (WO 2019/140196 A1; 7/18/2019; 9/28/23 IDS), Schlatter et al (Biotechnol Progress, 2005, 21: 122-133), Joshi et al (MARS, 2019, 11(7): 1254-1265), Dillon et al (MARS, 2017, 9(2): 213-230), and Yin et al (MARS, 2016, 8(8): 1467-1476, as applied to claims 29-31, 33-39, and 45 above, and further in view of Lionberger et al (WO 2019/075476 A2; 4/18/19).
Teachings of Gomez et al, Mchugh et al, Torres et al, Ali et al, Schlatter et al, Joshi et al, Dillon et al, and Yin et al are discussed above.
Gomez et al, Mchugh et al, Torres et al, Ali et al, Schlatter et al, Joshi et al, Dillon et al, and Yin et al do not specifically teach methods involving a nanofluidic chip. However, these deficiencies are made up in the teachings of Linoberger et al.
Lionberger et al teaches developing a new antibody production line can take many months of work and cost millions of dollars ([00219], in particular). Lionberger et al further teaches a microfluidic device (same as “chip”; see [00060]) that is able to screen and identify promising clones days after seeding individual clones that would offers significant time and cost advantages ([00219], in particular). Lionberger et further teaches the microfluidic devices comprising many (including 3,500) chambers ([00059] and [00510], in particular) in which analytes can be produced and measured ([0002], in particular). Lionberger et al further teaches analytes that are antibodies can be measured bound to a reporter that is a peptide epitope that binds the antibody ([00251], in particular). Lionberger et further teaches top analyte producers can be selected and exported from the microfluidic devices in order to expand the cells (“micro-objects”) ([0008], in particular). Lionberger et further teaches cells expressing analytes can be exported into well plates those wells can then be introduced to shaker flasks and then scaled-up ([00500], in particular). Lionberger et further teaches the temperature of the microfluidic device can be regulated ([00217], in particular).
One of ordinary skill in the art would have been motivated, with a reasonable expectation of success, to rapidly develop an optimized clone that generates an asymmetric multispecific antibody, such as that of Ali et al, by performing the combined method of Gomez et al, Mchugh et al, Torres et al, Ali et al, Gomez et al, Mchugh et al, Torres et al, Ali et al, Schlatter et al, Joshi et al, Dillon et al, and Yin et al wherein many different cultured clonally-derived cell lines expressing the asymmetric multispecific antibody are plated as single cell clones cultured in many distinct chambers of a microfluidic device of Lioberger et al, wherein the cells are cultured in medium at the temperatures and time points of the combined method, and amounts of asymmetric multispecific antibody products (and polypeptide chains thereof) produced by each clone are determined and compared at time points of the combined method, and those clonally derived cells that exhibits a culture condition that results in optimal asymmetric multispecific antibody production with reduced expression of product-related impurities of unpaired or mis-paired long heavy chains (as taught by Gomez et al) are selected and exported (as taught by Lionberger et al) any time cells that are identified as exhibiting a culture condition that results in optimal asymmetric multispecific antibody production – including after day 6 (after the three days at lower temperature of the combined method) into multi-wells of plates (such as those described on right column on page 2931 of Gomez et al), shaker flasks, and then scaled-up because the microfluidic device of Lionberger et al has the ability to culture antibody-producing cells at optimized temperatures and has the benefit of analyzing thousands of clones at a time for optimal antibody production. This is an example of prior art elements according to known methods to yield predictable results. This is further an example of use of known technique to improve similar methods in the same way. This is further drawn to some teaching, suggestion, or motivation in the prior art that would have led one of ordinary skill to combine prior art reference teachings to arrive at the claimed invention.
Therefore, the invention as a whole would have been prima facie obvious to one of ordinary skill in the art, absent unexpected results.
Conclusion
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