Professor of Immunology and Allergy at Imperial College London and 
European Academy of Allergy and Clinical Immunology (EAACI) Secretary General

Mohamed Shamji, PhD

PQ Grass Allergy Immunotherapy: Shared Decision-Making and What's Next, With Mohamed Shamji, PhD

View part 1 of our conversation with Shamji here.

With 6-injection PQ Grass 27,600 SU now backed by mechanistic and clinical data — including a 22.5% improvement in Combined Symptom Medication Score over placebo (

 <.00004) across pooled analyses of PQG309 and PQG306 (n = 75; PQ Grass, n = 40; placebo, n = 35), atop a placebo response commonly reaching 50% — the conversation around allergen immunotherapy is shifting from whether these treatments work to how clinicians and patients choose among an expanding set of options.

In the second part of our conversation with Mohamed Shamji, PhD, Professor of Immunology and Allergy at Imperial College London and Secretary General of the European Academy of Allergy and Clinical Immunology, at the 

American Academy of Allergy, Asthma & Immunology (AAAAI)

 2026 Annual Meeting held in Philadelphia, Pennsylvania, the focus turned to shared decision-making, the evidence gaps he most wants to see addressed, and the broader preventive potential of immunotherapy. 

Shamji was emphatic that treatment selection — among subcutaneous, sublingual, and accelerated pre-seasonal regimens like PQ Grass — must be driven by patient preference and lifestyle rather than physician default. Some patients find the structured clinic visit commitment of subcutaneous immunotherapy reassuring; others, particularly frequent travelers or those unable to keep regular appointments, are better served by home-based sublingual tablets. Adherence, he noted, is a persistent challenge across all AIT modalities — paradoxically, in part because immunotherapy works: patients who become symptom-free during treatment may stop taking it, just as they might stop a short course of antihistamines once symptoms resolve. The 6-injection model addresses this directly by compressing the entire pre-seasonal course into a small number of clinic visits, removing the daily compliance burden entirely. For pediatric patients, he added, needle aversion introduces an additional layer of complexity that makes route of administration a particularly important part of the shared decision.

On evidence gaps, Shamji identified objective predictive biomarkers as the priority he most wants to see developed alongside PQ Grass. The mechanistic data from PQG309 and PQG306 already demonstrate a clear tolerogenic immune signature — with statistically significant induction of sIgG, sIgG4, sIgA1, and sIgA2 (

 <.01), functional inhibition of allergen-IgE complex binding to B cells pre- and post-season (

 <.01 respectively), and suppression of Th2 and Th2A proliferation (

 <.05) — but translating those signals into validated, patient-facing biomarkers that can demonstrate treatment trajectory in real time remains an unmet need his group at Imperial is actively working toward. 

Finally, Shamji broadened the frame to immunotherapy's preventive dimension — its established ability to prevent new sensitizations and reduce progression to asthma — and previewed early data from his group on virus-like particles expressing the Fel d 1 molecule for cat allergy, which showed promising safety and efficacy in a first-in-human study, pointing toward a new generation of precision immunotherapy platforms he described as the genuinely exciting frontier of the field.

Shamji’s disclosure information was not available.

Layhadi J, Starchenka S, de Kam PJ, et al. PQ Grass 27600 SU effectively induces tolerogenic properties through modulation of humoral and cellular immune responses for the treatment of seasonal allergic rhinitis. Presented at: AAAAI 2026 Annual Meeting, February 27-March 2, Philadelphia, Pennsylvania. Abstract #L77

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Shamji shared the factors influencing which treatments are best for each patient and further research he'd like to see.

PQ Grass: Convenient Symptom Relief in Seasonal Allergic Rhinitis, With Mohamed Shamji, PhD

PQ Grass: Convenient Symptom Relief in Seasonal Allergic Rhinitis, With Mohamed Shamji, MD

PQ Grass 27600 SU, a chemically modified allergen preparation delivering just 6 subcutaneous injections pre-seasonally has demonstrated both clinically meaningful symptom reduction and broad immune tolerance induction according to new data presented at the 

 2026 Annual Meeting held in Philadelphia, Pennsylvania, by Mohamed Shamji, PhD, Professor of Immunology and Allergy at Imperial College London and secretary general at European Academy of Allergy and Clinical Immunology.

The data come from pooled analyses across 2 clinical trials, PQG309 and PQG306, evaluating PQ Grass 27,600 SU (a polymerized, chemically modified extract of 13 grass species) in patients with seasonal allergic rhinitis, with or without asthma (n = 75; PQ Grass, n = 40; placebo, n = 35). To discuss the findings and their implications for the future of allergen immunotherapy, we sat down with Shamji during the meeting to learn more about the clinical meaningfulness of the study findings. The study yielded a 22.5% improvement (

 <.00004) in the Combined Symptom Medication Score over placebo in a large AIT trial, its primary end point, atop a placebo response that itself commonly reaches 50%, meaning patients are experiencing roughly a 74% total reduction in symptoms — from 6 injections, with a adherence burden that bears no comparison to the 60-clinic-visit commitment of conventional 3-year subcutaneous or daily sublingual immunotherapy.

Mechanistically, PQ Grass induced robust systemic increases in grass pollen-specific blocking antibodies — sIgG (

 <.01) compared to placebo, measured both pre- and post-pollen season. Functionally, serum from treated patients significantly inhibited allergen-IgE complex binding to B cells pre-season (

 <.01). At the cellular level, PQ Grass suppressed proliferation of both Th2 (

 <.05) effector subsets, with trends toward reduced Tfh and IL-21+ Tfh cell proliferation and a positive trend in memory Treg induction — together painting a tolerogenic profile consistent with sustained clinical benefit and supporting PQ Grass as a viable accelerated-course alternative to conventional immunotherapy schedules.

“Patients only have 6 shots, and they really feel better. They have reduced symptoms during the pollen season. They take less risky medications like antihistamine or nasal steroids. And I think that's very important and very meaningful for the patients,” Shamji said.

Shamji’s disclosure information was not available. 

Shamji discussed the advantages of PQ grass over conventional immunotherapy at AAAAI 2026.

Mohamed Shamji, PhD

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