1.1 Sublingual immunotherapy (SLIT) (Table S1)
Three studies, a RDBPC19 and a
follow-up28 conducted by the same team, and a
prospective cohort22, investigated SLIT for the
treatment of PFA or LTP syndromes. The first two studies used hazelnut
extract standardized in the major allergens Cor a 1 and Cor a 8 in 12
and 7 adults with hazelnut allergy, respectively. The third study
investigated the effect of Pru p 3 SLIT in 29 children and adults with
LTP syndrome, including 5 patients with almond allergy, 5 with walnut,
10 with hazelnut, and 1 with cashew allergy. Hazelnut studies required a
DBPCFC at baseline, while the Pru p 3 study relied on history. The RDBPC
study included 12 patients in placebo, the follow-up study used baseline
assessment as the comparator, and the real-life cohort included 13
patients who followed the standard of care/avoidance (SOC). In all three
studies, SLIT started with a build-up phase and gradual escalations
until maintenance dose was reached (13,25 mg of total hazelnut protein,
corresponding to 24,34 μg of Cor a 8 and 37,63 μg of Cor a 1 in the
hazelnut-SLIT, and 12,5 μg of Pru p 3 in the Pru p 3-SLIT). The time of
intervention varied from 8 weeks 19 to 1 year22. The primary outcome in all studies was the
effectiveness of SLIT, and was assessed by the changes in Eliciting Dose
(ED) during the exit DBPCFC19,28, or by OFCs to
unpeeled peach and nuts22. Hazelnut
SLIT19,28 was successful in increasing ED and induced
immunological changes in a time-depended way. More than 50% of patients
with PF- or LTP-allergy passed an exit DBPCFC to 20 gr of hazelnut after
at least 8 weeks of treatment. On the contrary, the effectiveness of Pru
p 3 SLIT for a year on LTP- allergy to hazelnut was assessed in only 3
of the 10 hazelnut allergic patients, and one of them passed an exit OFC
to 14 gr of nut. This could be attributed to the lowest maintenance
dose, or to the inability of Pru p 3 to cross-desensitize Cor a
822. Regarding safety, SLIT was mainly associated with
oral pruritus. No epinephrine administrations were reported.
Because of the favorable safety profile, more studies are needed to
investigate if SLIT could represent an effective option for
desensitizing patients with PFAS or LTPS to tree nuts.