Model 1
remark - define model-specific commands 
COMMANDS 
NFUNCTIONS 3
NDERIVATIVES 5
NPARAMETERS 12
PNAMES  'Vc', 'kelA', 'kptA', 'ktpA', 'kint', 'kdeg', 'KDA','Rtot0','kelB','kptB','ktpB','KDB'
NCON 1
END
 
remark - define temporary variables
TEMPORARY 
T=X
Dose1=CON(1)
 
remark - C0 = 0.00343
C0= 0
RC0=Rtot0*C0/(KDA+C0)
Ctot0=RC0+C0
AT0=kptA*Vc*C0/ktpA
kepo=kint*RC0+kelA*C0
ksyn=(kint-kdeg)*RC0+kdeg*Rtot0
 
END 
 
remark - define initial conditions for differential equations
START 
 
 
Z(1) = Ctot0
Z(2) = AT0
Z(3) = Dose1/Vc
Z(4) = 0
Z(5) = Rtot0
 
 
END
 
remark - define differential equations
DIFFERENTIAL 
 
CtotA = Z(1)
CtotB = Z(3)
Rtot = Z(5)
aA=CtotA/Rtot
aB=CtotB/Rtot
kA=KDA/Rtot
kB=KDB/Rtot
remark - finding of the root of the polynomial using the bisection method.
Nmax=54 
acc=10**(-16) 
zlow=0 
zhigh=min(1,aA+aB) 
if kA = kB then
 b=-(1+aA+aB+kA) 
 c=aA+aB 
 flow=zlow**2+b*zlow+c 
 fhigh=zhigh**2+b*zhigh+c 
else
 b=-(2+kA+kB+aA+aB) 
 c=1+2*aA+2*aB+kA+kB+kB*aA+kA*aB+kA*kB 
 d=-(kB*aA+kA*aB+aA+aB) 
 flow=zlow**3+b*zlow**2+c*zlow+d 
 fhigh=zhigh**3+b*zhigh**2+c*zhigh+d 
endif
 DO n=0 to Nmax
  if zhigh-zlow < acc then
      GOTO CONTINUE
  endif
  zmid=(zlow+zhigh)/2 
  if kA = kB then
    fmid=zmid**2+b*zmid+c 
  else
    fmid=zmid**3+b*zmid**2+c*zmid+d 
  endif
  if fmid=0 then
    GOTO CONTINUE
  else
   if flow*fmid>0 then
     zlow=zmid 
     flow=fmid 
   else
     zhigh=zmid 
     fhigh=zmid 
   endif 
  endif
 NEXT
CONTINUE:
 zend=zmid 
CA=CtotA*KDA/(KDA+Rtot*(1-zend)) 
CB=CtotB*KDB/(KDB+Rtot*(1-zend)) 
 
 
DZ(1) = kepo-kint*Z(1)-(kelA+kptA-kint)*CA+ktpA*Z(2)/Vc
DZ(2) = kptA*CA*Vc-ktpA*Z(2)
DZ(3) =-kint*Z(3)-(kelB+kptB-kint)*CB+ktpB*Z(4)/Vc
DZ(4) = kptB*CB*Vc-ktpB*Z(4)
DZ(5) = ksyn-kdeg*Z(5)-(kint-kdeg)*(Z(1)+Z(3)-CA-CB)
 
END
 
remark - define algebraic functions
FUNCTION 1
F= CA
END
FUNCTION 2
F=CB
END
FUNCTION 3
F=(CA+CB)
END
 
remark - define any secondary parameters
remark - end of model
EOM