Table 1.
Overview of RCTs evaluated with early introduction of hen's egg.
| Trial | Study design | Primary outcome | Active group selection criteria | Active group/controls (n) included in the primary analysis | Allergen formulation (vehicle) | Intervention (control) | Limitations |
|---|---|---|---|---|---|---|---|
| EAT (39) | RCT | Prevalence of challenge-proven FA to HE or to other 5 foods in early-introduction group between 1 year and 3 years of age | 3-month-old exclusively breast-fed infants | 652/651 | Whole hard-boiled egg (not specified) | Early-introduction group (3–6 months of age): 4 g of egg protein/week (equivalent to 2 g of egg-white protein) (Standard-introduction group: introduced the same egg proteins amount after 6 month of age) | Low rate of per-protocol adherence in the early-introduction group. |
| PETIT (41) | DBRCT | Prevalence of HE allergy confirmed by OFC at 12 months of age | 4–5-month-old infants with AD, never orally exposed before to HE | 60/61 | Heated egg powder (squash, Japanese pumpkins) | Stepwise introduction of allergen From 6 to 9 months of age: 25 mg of egg proteins/daily; From 9 to 12 months of age: 125 mg of egg proteins/daily (Placebo from 6 to 12 months of age) | The study was early stopped because of a large group difference at the planned interim analysis. |
| STAR (42) | DBRCT | Diagnosis of IgE-mediated HE allergy by SPT and OFC at 12 months of age | 4-month-old infants with moderate-to-severe AD, never orally exposed before to HE | 42/35 | Pasteurized raw whole egg powder (infant rice cereal) | From 4 to 8 months of age: 0.9 g of egg protein/daily From 8 months of age: medically supervised cooked egg exposure (Placebo from 4 to 8 months of age) | - Recruitment was early stopped for logistic reason, without reaching the sample size originally estimated. - 31% of active group patients stopped egg powder ingestion due to allergic reactions. |
| HEAP (43) | RCT | Defined HE sensitization by sIgE at 12 months of age | 4–6-month-old infants from general population with HE sIgE levels <0.35 kUA/L | 156/142 | Pasteurized egg white powder (solid baby food) | From recruitment to 12 months of age, 3 times/week: - 0.8 g in the first week - 1.6 g in the second week - 2.5 g from the third week of intervention to 12 months of age. (Placebo from recruitment to 12 months of age) |
- Recruitment was early stopped for allergic reaction in active group at first exposure to allergen. |
| STEP (44) | RCT | Diagnosis of IgE-mediated HE allergy and sensitization by OFC and SPT, respectively, at age 12 months | 4–6.5-month-old infants with atopic mothers and without history of allergic disease or previous egg ingestion | 407/413 | Pasteurized raw whole egg powder (carrot, pineapple, and rice powders) | From recruitment to 10 months of age: 0.4 g egg protein/daily From 10 months of age: cooked egg and egg-containing foods were included in diet of both groups. (Placebo from recruitment to 10 months of age) | - Inability to reach the planned sample size. - Relatively small amount of dietary egg. |
| BEAT (45) | DBRCT | Prevalence of HE sensitization confirmed by SPT at 12 months of age | 4–6-month-old infants no-sensitized to HE with a family history for allergy (at least one first-degree relative with allergic diseases) | 165/154 | Pasteurized whole egg powder (not specified) | From recruitment to 8 months of age: 350 mg egg protein/daily From 8 months of age: liberalized diet in active group and controls. (Placebo from recruitment to 8 months of age) | - Relatively small amount of dietary egg. - Impossibility to challenge all infants with possible egg allergy at 12 months of age. |
FA, Food allergy; HE, hen's egg; DBRCT, double-blind randomized controlled trial; RCT, randomized controlled trial; sIgE, specific IgE; EAT, Enquiring About Tolerance; PETIT, Prevention of Egg Allergy with Tiny Amount Intake; STAR, Solid Timing for Allergy Research; HEAP, Hen's Egg Allergy Prevention; STEP, Study Starting Time of Egg Protein; BEAT, Beating Egg Allergy Trial; OFC, oral food challenge; AD, atopic dermatitis; SPT, skin prick test.