P.P. is a 19-year-old adolescent (body weight 65kg) with a medical history of persistent asthma. His current drug profile includes: 

• Fluticasone/Salmeterol 500/50 mcg 1 puff BD; 
• Salbutamol 1-2 puffs Q4-6H PRN for shortness of breath. 

P.P. has had two asthma exacerbations in the past year. PP's most recent pulmonary function testing is as follows: 

• Forced expiratory volume in 1 second ("FEV1") 54% of predicted, 
• Forced vital capacity ("FVC") 78% of predicted
• FEV1/FVC 0.64 (ref. > 0.7)
• Peak expiratory flow (personal best) 450 L/minute (ref. 400-700 L/minute) 

Over the past 4 weeks, P.P. states that he has been using the salbutamol inhaler twice weekly and waking once per week because of asthma symptoms. However, P.P. has not been hospitalised due to the worsening in symptoms. 

a) Assess the severity level of P.P.'s asthma according to the Global Initiative for Asthma ("GINA") guidelines. Suggest ONE pharmacist intervention on P.P.'s drug regimen. (2 marks) 

b) Upon the modification of P.P.'s regimen, he is still experiencing worsening of asthma symptoms. P.P. is referred to a respiratory physician with the following tests conducted: 

Immunoglobulin E (“IgE”) 2290 IU/mL, (ref 0-100 IU/mL) fractional exhaled nitric oxide ("FeNO") 55 ppb, (ref. <25 ppb) blood eosinophil count 190 cells/mm3. (ref. 30-350 cells/mm3) 

P.P.'s is subsequently diagnosed with severe eosinophilic asthma with phenotype of Type 2 airway inflammation after 3 months. List at least TWO biologic therapies of different drug classes or mechanism of action, specifying BOTH drug class and drug name, which can be used as an add-on therapy in P.P.'s asthma. (4 marks) 

c) P.P.'s case medical officer has prescribed Reslizumab IV 19 5 mg every 4 week but you just realised that it is not yet registered and available in Hong Kong. Suggest TWO alternate treatment options to P.P.'s case medical officer under this situation. (2 marks) 

d) P.P.'s case medical officer made a final decision to prescribe Mepolizumab SC 100 mg every 4 week which is a registered drug item in Hong Kong. Suggest the treatment duration of Mepolizumab IV for P.P. before the assessment of clinical response. (1 mark) 

e) P.P.'s case medical officer has made a drug information enquiry to Pharmacy regarding the treatment response to Mepolizumab. List at least TWO factors which may predict good asthma response to Mepolizumab. (3 marks) 

f) After a year, you assessed that P.P. has achieved good asthma response to Mepolizumab therapy. Other than inhaler technique and drug compliance, suggest any future treatment plan for P.P.'s severe asthma treatment. (3 marks)