Jose Gamboa-Avila v. Secretary of Health and Human Services

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.
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GAMBOA-AVILA v. HHS 2
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.
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GAMBOA-AVILA v. HHS 3
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.
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GAMBOA-AVILA v. HHS 4
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
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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
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GAMBOA-AVILA v. HHS 6
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]
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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,
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GAMBOA-AVILA v. HHS 8
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
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GAMBOA-AVILA v. HHS 9
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).
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GAMBOA-AVILA v. HHS 10
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.
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