Aw Biologicals

Question 0

Biologicals are isolated from 3 sources…

Answer 0

Humans
Microorganism
Animal

Question 1

Three eg of biologicals

Answer 1

Vaccines
Recombinant proteins and peptides
Gene therapy

Question 2

Why are bio at the front of the market.

Answer 2

They’ve already evolved to rurally bind to a particular target which is an advantage

Question 3

May be used to treat conductions where there is nothing else available:

Answer 3

-oncology -rheumatology -cardiology

Question 4

In 2006 the bio market was % of sales and worth…

Answer 4

10% and worth £35 bn

Question 5

Earliest example of a biological

Answer 5

Insulin

Question 6

Fuzeon

Answer 6

Aniti HIV fuzeon inhibitor

Question 7

Fuzeon works by

Answer 7

Blocking entry of HIV into CD4 or T cells

Question 8

Fuzeon mimics

Answer 8

GP41 on the surface of the virus, parenting normal fusion.

Question 9

Why can we used fuzeon with other theroapies?

Answer 9

Targets alternative mechanism

Question 10

Fuzeon is composed of ….. And is produced…

Answer 10

36 amino acids, produced synthetically

Question 11

HIV membrane contains trimeric glycoprotein spikes containing …

Answer 11

gp41 and gp120 subunits

Question 12

Fusion begins with ….. binding to CD4 chemikine receptor and co receptor

Answer 12

Gp120

Question 13

Binding to CD4 chemokine receptor causes

Answer 13

Conformational change in gp120 - move aside exposing GP41

Question 14

GP41 is made up of …

Answer 14

two heptad repeat domains, HR1 (tightly wound could) and HR2 (random chain - closest to virus)

Question 15

How do the membrane come into contact?

Answer 15

H2 coils into h1, zipping together, punches a fusion pre into both membranes, allows HIV caspid to pass

Question 16

Fuzeon mimics… Which has the what effect…

Answer 16

H2 region Of gp41

Prevents zipping so membranes never come into contact

Question 17

Advantages of fuzeon

Answer 17

• Revolutionary class of HIV therapy
• unique mode of action - no cross resistance with other classes
• Shows antiviral activity in vitro against wild-type virus as well as virus resistant to all three of the currently available classes of antiretroviral

Question 18

Disadvantages of fuzeon

Answer 18

Treatment is £13000 a year

Administered by sub cut bd

Question 19

Why this admin technique

Answer 19

Not orally bio, does not obey lipinksis rules

Many ionisable groups so rapidly excreted and endogenous proteases degrade so short half life

Question 20

Problems with biologicals

Answer 20

Proteins and peptides are not good drug like molecules

Question 21

Why are we particularly concerned with extending half life?

Answer 21

Reduced cost of therapy

Improve quality of life

Question 22

Four main ways to produce biologicals….

Answer 22

• Synthetically (peptides such as Fuzeon)
• Human cell lines
• Yeast cells (humanised)
  -Bacterial cells

Question 23

Compare yield and PTM of human, yeast, baeria

Answer 23

Human, retains PTM, low yeild
Yeast, retains PTM, better yeild
Bacterial does not retain PTM but has much better yield

Question 24

Most common method of production at the moment?

Answer 24

Bacterial

Question 25

Can only produce blogs also synthetically if...

Answer 25

Small insulin, fuzeon, 6000 DA. Mab are often 100000

Question 26

Four PTMs

Answer 26

-Phosphorylation -Sulfation -Acylation -Glycosylation (addition of carbohydrates

Question 27

Two major gylcosylatiosn

Answer 27

O and n linked

Question 28

O linked is important .....

Answer 28

protein targeting to specific receptors Eg blood antigens are o linked

Question 29

N linked is important becuase...

Answer 29

N-linked glycosylation plays important roles in protein regulation and serum half-life N-linked carbohydrates play an important role in the PK properties of Biological Therapeutics

Question 30

Where can n link?

Answer 30

Asparagine

Question 31

Where can o link

Answer 31

Serene

Question 32

Why does adding a carb change the PK so much?

Answer 32

They are about the same size as the protein

Question 33

Can you repeat gylcosylatiosn in the lab?

Answer 33

No, variety of sugars attached in variety of ways, cannot repeat synthetically at scale

Question 34

Filgrastin is used.....

Answer 34

After chemo to replenish marrow (neutropenia)

Question 35

Class of filgrastin?

Answer 35

Filgrastim is a human granulocyte colony-stimulating factor (G-CSF).

Question 36

Filgrastin is a ..... aa protein made by

Answer 36

175 Recombinant DNA technology 18800 da

Question 37

Colony stimulating factors are.... Which act on...

Answer 37

Glycoproteins, which act on hematopoietic - binding and stimulating proliferation, differentiation commitment, and some end-cell functional activation

Question 38

Dose and frequency of filgrastin varies as per caner but.

Answer 38

Dosing ranges: - 3 – 70 micrograms DAILY | Each regim lasts between 7 days to 1 month.

Question 39

Elimination half life of filgrastin

Answer 39

3.5 hours

Question 40

Bacterial production of filgrastin by

Answer 40

E. coli with the human colony stimulating factor gene inserted

Question 41

How does the ecoli made filgrastin differ from human

Answer 41

PTM- non glycosylated | Hence short half life

Question 42

Pegylation

Answer 42

PEGylation, is a process of attaching the strands of polyethylene glycol (PEG) polymer to molecules Typically 20-40 kDa

Question 43

Peg has lots of o in it, how does this work to our advantage?

Answer 43

Water surrounding increases size and mass of molecule even more, (reduced renal filtration and clearance of filgrastin) increases half life

Question 44

Immune advantage of PEG

Answer 44

Masks from immune system | reduced immunogenicity and antigenicity

Question 45

How do we achieve peg

Answer 45

incubation of a reactive derivative of PEG with the target macromolecule

Question 46

Five advantages of peg

Answer 46

* Improved drug solubility * Reduced dosage frequency, without diminished efficacy with potentially reduced toxicity * Extended circulating life * Increased drug stability * Enhanced protection from proteolytic degradation

Question 47

Two commercial advantages of peg

Answer 47

* Opportunities for new delivery formats and dosing regimens * Extended patent life of previously approved drugs

Question 48

Pegfilgrastim (NEULASTA)

Answer 48

covalent conjugate of recombinant methionyl human G-CSF (Filgrastim) and monomethoxypolyethylene glycol

Question 49

Admin of neulasata

Answer 49

Neulasta is administered by sub-cutaneous injection, ONCE A FORTNIGHT. 39kD ... Increased half life

Question 50

Other Glycoslation ideas being explored

Answer 50

Synthetic Albumin Polysialic acid Cellular gylcosylatiosn