Gamboa-Avila v. Hhs

• Court: Court of Appeals for the Federal Circuit
• Decided: February 11, 2026
• Docket: 24-1765
• Status: Published

Opinion

Case: 24-1765 Document: 54 Page: 1 Filed: 02/11/2026

United States Court of Appeals for the Federal Circuit ______________________

JOSE GAMBOA-AVILA, Petitioner-Appellant

v.

SECRETARY OF HEALTH AND HUMAN SERVICES, Respondent-Appellee ______________________

2024-1765 ______________________

Appeal from the United States Court of Federal Claims in No. 1:18-vv-00925-DAT, Judge David A. Tapp. ______________________

Decided: February 11, 2026 ______________________

CURTIS RANDAL WEBB, Monmouth, OR, argued for peti- tioner-appellant.

ALEC SAXE, Torts Branch, Civil Division, United States Department of Justice, Washington, DC, argued for re- spondent-appellee. Also represented by BRIAN M. BOYNTON, C. SALVATORE D'ALESSIO, COLLEEN HARTLEY, HEATHER LYNN PEARLMAN. ______________________

Before DYK, CHEN, and STOLL, Circuit Judges. Case: 24-1765 Document: 54 Page: 2 Filed: 02/11/2026

DYK, Circuit Judge. Petitioner-Appellant Jose Gamboa-Avila (“Mr. Gam- boa”) filed a petition for compensation under the National Vaccine Injury Compensation Program, 42 U.S.C. §§ 300aa-10 to 34 (“Vaccine Program”), in the Court of Fed- eral Claims (“Claims Court”), alleging that a pneumococcal conjugate vaccine (“PCV”) caused him to suffer from Guil- lain-Barré Syndrome (“GBS”). Because this is an off-Table case, Mr. Gamboa was re- quired to establish causation. A special master of the Claims Court found that Mr. Gamboa did not prove that PCV can cause GBS and was thus not entitled to compen- sation. On review, the Claims Court affirmed. Mr. Gam- boa appeals, arguing that the special master effectively required him to produce medical literature explicitly estab- lishing a link between PCV and GBS, which he argues is contrary to our holding in Althen v. Secretary of Health & Human Services, 418 F.3d 1274 (Fed. Cir. 2005). Because we conclude that the special master here ap- plied the proper evidentiary standard, we affirm. At the same time, we note that in these PCV cases, different spe- cial masters appear to have reached inconsistent results on identical facts. The Office of Special Masters should con- sider recommending, and the Claims Court should consider adopting, uniform related-case or other procedures to avoid such inconsistencies. BACKGROUND Mr. Gamboa received an injection of Prevnar 13, a PCV, on November 13, 2017. As a PCV, Prevnar 13 is cov- ered under the Vaccine Program. On November 27, 2017, he sought treatment for generalized body aches, a head- ache, night sweats, and numbness, all of which he reported experiencing since November 13. Mr. Gamboa continued to experience symptoms and seek medical care over the next few days, culminating in a hospitalization. Case: 24-1765 Document: 54 Page: 3 Filed: 02/11/2026

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Mr. Gamboa was diagnosed with GBS, an autoimmune dis- ease involving the loss of nerve-insulating myelin in the pe- ripheral nervous system, see App’x 226,1 and was treated during his hospitalization. He was discharged on Decem- ber 10, 2017. On June 27, 2018, Mr. Gamboa filed a petition for com- pensation under the Vaccine Program. Mr. Gamboa intro- duced several reports from an expert witness, Dr. Lawrence Steinman, advancing theories that compo- nents of PCV can cause GBS based on “molecular mimicry,” whereby certain PCV components mimic the molecules pre- sent in nerve myelin, causing an autoimmune response to the myelin. Dr. J. Lindsay Whitton, an expert witness on behalf of the Secretary of Health and Human Services, sub- mitted expert reports countering Dr. Steinman’s theories. A claimant must prove causation-in-fact for an off-Ta- ble injury by preponderant evidence of “(1) a medical theory causally connecting the vaccination and the injury; (2) a logical sequence of cause and effect showing that the vac- cination was the reason for the injury; and (3) a showing of a proximate temporal relationship between vaccination and injury.” Althen, 418 F.3d at 1278. The special master determined that Mr. Gamboa failed to carry his burden of proof under Althen prong one. App’x 27, 35. The special master analyzed each expert’s report and made findings with respect to the applicability and soundness of the evi- dence and methodologies relied upon by each expert. The special master found that elements of Dr. Steinman’s the- ory were unsupported by “reputable publications or stud- ies.” App’x 36. In particular, the special master noted the absence of literature specifically connecting the phospho- lipid components at the center of Dr. Steinman’s theory to GBS. The special master went on to analyze

1 Citations to “App’x” refer to the Corrected Appen- dix filed by Mr. Gamboa. Dkt. No. 36. Case: 24-1765 Document: 54 Page: 4 Filed: 02/11/2026

Dr. Steinman’s evidence in detail and concluded that his molecular-mimicry theory did not scientifically justify link- ing Prevnar 13 to GBS. Finding no causation under prong one, the special mas- ter did not reach the other Althen prongs or whether Mr. Gamboa was correctly diagnosed with GBS. Mr. Gam- boa sought review of the special master’s decision by the Claims Court. The Claims Court affirmed. Mr. Gamboa timely appealed. We have jurisdiction un- der 42 U.S.C. § 300aa-12(f). DISCUSSION I We review de novo the Claims Court’s denial of the mo- tion to review the special master’s decision. Lozano v. Sec’y of Health & Hum. Servs., 958 F.3d 1363, 1368 (Fed. Cir. 2020). We review de novo any questions of law, but we up- hold the special master’s factual findings unless they are arbitrary or capricious. Id.; see 42 U.S.C. § 300aa- 12(e)(2)(B). A A Vaccine Program claimant may establish a causal link between a vaccine and an injury in one of two ways. The first is by a presumption of causation, if the vaccine and injury combination is listed in the Vaccine Injury Ta- ble. Althen, 418 F.3d at 1278; see 42 U.S.C. § 300aa-14(a), (c); 42 C.F.R. § 100.3. The second is by proving causation- in-fact by a preponderance of the evidence. Althen, 418 F.3d at 1278; Boatmon v. Sec’y of Health & Hum. Servs., 941 F.3d 1351, 1359 (Fed. Cir. 2019); see 42 U.S.C. § 300aa-13(a)(1). The operative Vaccine Injury Table does not list PCVs with GBS in combination. 42 C.F.R. § 100.3. Mr. Gamboa must therefore prove causation-in-fact under Althen by showing “(1) a medical theory causally connect- ing the vaccination and the injury; (2) a logical sequence of Case: 24-1765 Document: 54 Page: 5 Filed: 02/11/2026

GAMBOA-AVILA v. HHS 5

cause and effect showing that the vaccination was the rea- son for the injury; and (3) a showing of a proximate tem- poral relationship between vaccination and injury.” Althen, 418 F.3d at 1278. Only Althen prong one is at issue in this appeal. Addressing the first prong of Althen before the special master, Mr. Gamboa presented molecular-mimicry theo- ries supported by Dr. Steinman’s expert reports. A related molecular-mimicry theory linking seasonal influenza vac- cines to GBS became widely accepted, and Health and Hu- man Services included the flu-vaccine–GBS combination in the Vaccine Injury Table. App’x 33; National Vaccine In- jury Compensation Program: Revisions to the Vaccine In- jury Table, 82 Fed. Reg. 6294, 6295 (Jan. 19, 2017). But Dr. Steinman cited no articles directly linking pneumococ- cal conjugate vaccines to GBS. He instead put forward sev- eral studies as offering indirect support for his theory, such as a study linking the phospholipid components at the cen- ter of his molecular-mimicry theory to an autoimmune re- sponse in multiple sclerosis and another study showing that the blood of GBS patients contained antibodies that are reactive to those phospholipid components. The special master concluded that Mr. Gamboa failed to satisfy Althen prong one by preponderant evidence. B Mr. Gamboa argues that the special master applied a higher evidentiary standard than Althen permits, requir- ing him to provide medical literature explicitly confirming that PCVs are causally linked to GBS. In Althen, we con- sidered a special master’s rejection of a Vaccine Program claim “because [the claimant] did not provide peer-re- viewed literature that demonstrated a suspected or poten- tial association between the tetanus toxoid vaccine and the alleged injuries.” Althen, 418 F.3d at 1277 (emphasis re- moved) (internal citations and quotations omitted). We held that the peer-reviewed literature requirement was Case: 24-1765 Document: 54 Page: 6 Filed: 02/11/2026

contrary to the Vaccine Program statute, as it “prevent[ed] the use of circumstantial evidence envisioned by the pre- ponderance standard and negat[ed] the system created by Congress.” Id. at 1280 (citing 42 U.S.C. § 300aa-13(a)(1)). “[T]he purpose of the Vaccine Act’s preponderance stand- ard is to allow the finding of causation in a field bereft of complete and direct proof of how vaccines affect the human body.” Id. We do not read the special master’s decision here to re- quire support of a causation theory with medical literature and conclude the special master’s analysis is consistent with Althen. To be sure, the special master relied on the absence of support in the medical literature for Dr. Stein- man’s theories. But Althen does not prohibit a special mas- ter from considering medical literature when weighing the scientific evidence underlying a claimant’s causation the- ory. Cases following Althen have confirmed that a “special master is entitled to require some indicia of reliability to support the assertion of the expert witness.” Moberly v. Sec’y of Health & Hum. Servs., 592 F.3d 1315, 1324 (Fed. Cir. 2010); Boatmon, 941 F.3d at 1360. A special master may weigh the fact that a “proposed mechanism had never been tested in any peer-reviewed study” and may properly consider the weakness of medical literature support when evaluating the overall reliability of scientific evidence. Moberly, 592 F.3d at 1324; see Broekelschen v. Sec’y of Health & Hum. Servs., 618 F.3d 1339, 1350–51 (Fed. Cir. 2010) (affirming a special master’s no-causation determination where the claimant’s supporting evidence, “a literature review based on two papers from the early 1950s,” was “quite weak”). The special master here, as permitted by our cases, only relied on the absence of medical literature as one fea- ture in his analysis, relying on other core “foundational de- ficiencies” in the theory unrelated to the absence of medical literature. App’x 36–39. For example, he remarked that “Dr. Steinman cannot explain convincingly why the [PCV] Case: 24-1765 Document: 54 Page: 7 Filed: 02/11/2026

GAMBOA-AVILA v. HHS 7

would be more likely to cause GBS than its wild bacterial infectious analog (which unquestionably is not so associ- ated).” App’x 36 (emphasis in original). He noted that Dr. Steinman could only show that his proposed autoim- mune targets were present in myelin without demonstrat- ing why they were more likely than other structures to cause autoimmune responses. See id. (“It is simply specu- lative to propose that GBS could be mediated by an attack on this target, based solely on the logic that the myelin con- tains it—and the degree of speculation is highlighted by the comparatively larger amount of evidence that associate gangliosides as a likely target.” (emphasis in original)) And the special master observed that much of Dr. Steinman’s evidence was related to multiple sclerosis, not GBS. Id. We conclude that the special master did not apply a standard inconsistent with Althen. II At oral argument, Mr. Gamboa noted that the special master’s findings in this case are inconsistent with those reached by other special masters on identical evidence in other cases and argued that this somehow established an Althen violation. In Boatmon, we held that it was not ar- bitrary and capricious for a special master to “ma[ke] no attempt to distinguish the instant case” from “the other cases reaching opposite conclusions.” Boatmon, 941 F.3d at 1358 (internal quotations omitted). While we reject Mr. Gamboa’s theory as unsupported, we are troubled by inconsistent findings on identical facts by different special masters. The special master here noted that his analysis in Mr. Gamboa’s case “recapitulates” his earlier findings in other cases alleging a PCV-GBS link based on the same studies cited here. App’x 42 (citing Bielak v. Sec’y of Health & Hum. Servs., No. 18-761V, 2022 WL 18058244, at *15– 17, 32 (Fed. Cl. Spec. Mstr. Dec. 9, 2022), released publicly as 2023 WL 35509 (Fed. Cl. Spec. Mstr. Jan. 3, 2023)); Trollinger v. Sec’y of Health & Hum. Servs., No. 16-473V, Case: 24-1765 Document: 54 Page: 8 Filed: 02/11/2026

2023 WL 2521912, at *28–29 (Fed. Cl. Spec. Mstr. Feb. 17, 2023). Recognizing that his findings were outliers as com- pared to other special masters, he further observed that the same scientific evidence he rejected had successfully per- suaded other special masters of a PCV-GBS causal link. See id. (citing Gross v. Sec’y of Health & Hum. Servs., No. 17-1075V, 2022 WL 9669651, at *15–17, 28 (Fed. Cl. Spec. Mstr. Sept. 22, 2022); Pierson v. Sec’y of Health & Hum. Servs., No. 17-1136V, 2022 WL 322836 (Fed. Cl. Spec. Mstr. Jan. 19, 2022)). The special master acknowledged the inconsistency in assessments by different special mas- ters of the same causation theory and that he is the only special master to find no causation.2 In other words, for a claimant such as Mr. Gamboa, the identity of the special master assigned to his case determines the outcome, a re- sult that is both arbitrary and unfair. As Boatmon demon- strates, this is not an isolated example of that problem. See Boatmon, 941 F.3d at 1358–59. Generally, in federal civil litigation, there are mecha- nisms designed to minimize inconsistent results on identi- cal facts. For example, for related cases filed within the same district, district courts have established local rules that require the assignment of related cases to the same judge. See, e.g., D.D.C. L. Civ. R. 40.5; E.D. Tex. L. Civ. R. 42.3

2 The special master stated: “And while special mas- ters often take refuge in the legal truism that their col- leagues’ determinations do not bind them, [Mr. Gamboa] not-unreasonably notes the fact that I am (so far) alone in my negative assessment of this causation theory.” App’x 42. 3 Where actions are brought in different districts sharing common questions of fact, a party may seek Case: 24-1765 Document: 54 Page: 9 Filed: 02/11/2026

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The Office of Special Masters (“OSM”) is empowered by statute to recommend rules to the Claims Court for adop- tion under its rulemaking authority to “provide for a less- adversarial, expeditious, and informal proceeding for the resolution of petitions.” 42 U.S.C. § 300aa-12(d)(2)(A); see 28 U.S.C. § 2071. The special masters have recommended, and the Claims Court has established, Vaccine Rules that govern proceedings under the Vaccine Program. See gen- erally Vaccine Rules, Rules of Ct. of Fed. Claims app. B. Although the Claims Court has not adopted a related- case rule, the OSM has consolidated omnibus proceedings to promote consistency in related cases. See, e.g., Snyder v. Sec’y of Dep’t of Health & Hum. Servs., No. 01-162V, 2009 WL 332044, at *2 (Fed. Cl. Spec. Mstr. Feb. 12, 2009) (discussing the basis of the OSM’s authority to conduct om- nibus proceedings in its authority to “develop expertise in the complex medical and scientific issues involved in actual causation claims” and to “apply this expertise to the

transfer under 28 U.S.C. § 1404(a), under which courts con- sider whether the potential for consolidation with a related case is “in the interest of justice.” See, e.g., Cont’l Grain Co. v. The FBL-585, 364 U.S. 19, 20, 26 (1960); In re Volkswagen of Am., Inc., 566 F.3d 1349, 1351 (Fed. Cir. 2009) (“In this case, the existence of multiple lawsuits in- volving the same issues is a paramount consideration when determining whether a transfer is in the interest of jus- tice.”). Multidistrict litigation (MDL) also allows common pre- trial issues to be consolidated in a single court. 28 U.S.C. § 1407(a); see also 15 Wright & Miller, Federal Practice & Procedure §§ 3861–3868 (4th ed.) For example, MDL is of- ten useful to resolve common factual issues related to cau- sation. See, e.g., In re Welding Rod Prods. Liab. Litig., 269 F. Supp. 2d 1365, 1366–67 (J.P.M.L. 2003). Case: 24-1765 Document: 54 Page: 10 Filed: 02/11/2026

resolution of other cases”). For example, in 2002, the OSM instituted an “Omnibus Autism Proceeding” to “inquire into the general causation issues involved in these cases” and to enter the evidentiary record into an “Autism Master File.” Autism General Order #1, 2002 WL 31696785, at *3 (Fed. Cl. Spec. Mstr. July 3, 2002); see, e.g., Cedillo v. Sec’y of Health & Hum. Servs., No. 98-916V, 2009 WL 331968 (Fed. Cl. Spec. Mstr. Feb. 12, 2009); King v. Sec’y of Health & Hum. Servs., No. 03-589V, 2010 WL 892296 (Fed. Cl. Spec. Mstr. Mar. 12, 2010). In light of the admitted inconsistencies in the types of cases involved here, the OSM should consider recommend- ing, and the Claims Court should consider adopting, a re- lated-case rule or other mechanisms to avoid inconsistent rulings of the special masters. CONCLUSION Although we are troubled by the inconsistent factual findings among the special masters on central issues pre- sented in this case, we conclude that the special master here did not impose an improper evidentiary burden on Mr. Gamboa. Accordingly, we affirm. AFFIRMED COSTS No costs.