Modeling the effects of omalizumab over 5 years among patients with moderate-to-severe persistent allergic asthma

Abstract

Objective:

Omalizumab is a monoclonal antibody indicated for adults and adolescents with moderate-to-severe persistent allergic asthma whose symptoms are inadequately controlled with inhaled corticosteroids. Omalizumab has been demonstrated to improve health outcomes of asthmatic patients as compared to placebo. However, to date, the trials conducted have been relatively short (less than 1 year) and have been restricted to a limited set of patients who met the clinical study criteria. This study examined the expected effects of omalizumab over 5 years on a representative sample of all patients eligible for omalizumab in the US.

Methods:

The Archimedes Asthma Model was used to simulate the following treatment scenarios for US patients age 12 and older with moderate-to-severe persistent allergic asthma: (1) Current asthma treatment (CAT) (treatment according to National Heart, Lung, and Blood Institute (NHLBI) guidelines, without use of omalizumab, and with adherence levels as observed in the National Asthma Survey); (2) Guideline asthma treatment (GAT) without omalizumab (NHLBI guidelines without use of omalizumab, assuming perfect adherence); (3) GAT plus omalizumab; and (4) GAT plus omalizumab with steroid reduction. The simulation was run for 5 years.

Main outcome measures:

Symptom days, asthma exacerbations, emergency room/urgent care (ER/UC) visits, hospitalizations, and medication use.

Results:

For the full simulated population of omalizumab-eligible patients, the simulation forecasted that omalizumab would decrease cumulative exacerbations by 30%, ER/UC visits by 37%, and hospitalizations by 38% over 5 years. Among responders to omalizumab, assuming that 60.5% of patients respond, the results suggest that omalizumab would decrease cumulative exacerbations by 50%, ER/UC visits by 62%, and hospitalizations by 63% over 5 years.

In addition, the simulation predicted that omalizumab would allow 45% of patients who are taking more than the minimum steroid dose to reduce their steroid dose, while maintaining similar asthma control as achieved in the GAT plus omalizumab arm (no steroid dose reduction) and better asthma control than following treatment protocols that do not include omalizumab.

Conclusion:

Based on the results of this simulation, omalizumab is effective for those who respond, reducing serious events by more than 50% among the responder group, while also allowing many patients to reduce their steroid dose.

Key words::

• Anti-IgE
• Asthma
• Computer simulation
• Omalizumab

Transparency

Declaration of funding

This study was supported by Novartis Pharmaceuticals Corporation, East Hanover, NJ and Genentech, Inc., South San Francisco, CA.

Declaration of financial/other relationships

H.L.G., A.S., and P.A. are employees of Archimedes, Inc., who were paid consultants to Novartis in connection with the development of the manuscript. E.L.S. and J.Z. are employees of Novartis Pharmaceuticals Corporation, which co-promotes Xolair (omalizumab).

Acknowledgments

The authors would like to thank Barbara Peskin and Kathleen Thompson for their assistance with the modeling work and their contributions to this manuscript.

Notes

* Of the 1071 people in these trials, the imputation only used the people who matched the NAS people most closely, which turned out to be 484 people.

* Because the simulation was perfectly controlled (the same set of people were modeled in each arm), it was not necessary to adjust for control variables in the analysis.

* Xolair is a registered trade name of Genentech, Inc., USA and Novartis Pharmaceuticals Corporation, USA.