Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

PT4024 > RNA Therapeutics > Flashcards

RNA Therapeutics Flashcards

1
Q

Main differences between small molecule drugs and macromolecular drugs

A

→ Small molecule drugs have a lower mw, are more stable, are less immunogenic, are more easily purified, manufacture is readily scaled up, have simpler structures, and are often amenable to oral admin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Approved ASOs in the EU

A

Spinraza, Waylivra

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

5 siRNA drugs approved

A

Patisiran, Givosiran, Inclisiran, Lumasiran, Vutrisiran

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Challenges for pharmaceutical use of nucleic acids?

A
  • Safe & effective delivery to correct target (polyanions, large size, inability to enter cells on their own)
  • Delivery systems capable of targeting tissues beyond the liver
  • Pre-existing immunity (e.g. anti-PEG Abs, viral vectors)
  • Control over dose & duration of therapeutic effect
  • Limited admin (low oral bioavailability)
  • Shelf-life stability & price
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Chemical modifications can protect nucleic acid-based therapies against…

A

host immunogenic responses to RNA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are siRNAs?

A

short dsRNAs (21-25 nt), 2 nt overhangs at 3’ ends
generated from long dsRNA fragments or chemically synthesised

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

siRNAs efficiently load mRNAs onto __ , which leads to mRNA cleavage

A

RISC complex

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Advantage of siRNAs

A

They have near perfect complementarity with the target sequence - very specific, less immunogenic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

The first non-viral siRNA medicine to reach the market

A

Patisiran (Onpattro)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Patisiran

A

siRNA-LNP approved for Transthyrin (TTR) amyloidosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Patisiran is a very effective way to…

A

reduce serum levels of misfolded amyloid protein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are a simple solution to the siRNA delivery problem for hepatocytes?

A

GalNAc-siRNA conjugates

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

N-acetyl galactosamine (GalNAc) has a high affinity for the __

A

asialoglycoprotein receptor (ASGPR) expressed on hepatocytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

GalNAc-siRNA conjugates allow for…

A

s.c. admin & less frequent dosing

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is Givosiran (Givlaari)?

A

FDA approved for adults with acute hepatic porphyria

→ GalNAc-siRNA conjugate that targets aminolaevulinic acid synthase 1 (ALAS1) mRNA to reduce toxic metabolites

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

3 common mechanisms utilised by ASOs

A
  1. mRNA target degradation via recruitment of RNase H enzyme
  2. Alternative splicing modification to include or exclude exons
  3. miRNA inhibition to inhibit miRNA binding to its target mRNA
17
Q

What is Spinraza (Nusinersen)?

A

ASO for treatment of spinal muscular atrophy

18
Q

How does Spinraza treat SMA?

A

Targets SMN2 pre-mRNA
- Potent inducer of SMN2 exon 7 inclusion and SMN protein expression

19
Q

How is Spinraza administered?

A

Intrathecally

20
Q

Most developments in ASO therapeutics are directed at __ diseases

A

neurodegenerative

21
Q

Advantages of mRNA-based therapy

A
  • Dose control
  • No risk of insertional mutagenesis
  • Suitable for non-viral delivery by virtue of mRNA cytoplasmic activity
  • Enables expression of any therapeutic protein
22
Q

Structural modifications of mRNA

A
  • 5’ cap modifications
  • Coding region (to improve translation)
  • PolyA tail (stability)
  • 5’ and 3’ UTR (regulates molecule specificity)
  • Modified dNTP (modulates innate immunity)
23
Q

Why is Haemophilia B a good candidate for protein replacement therapy via mRNA treatment?

A

because it is caused by a single defective protein (Factor IX) normally produced by liver

24
Q

mRNA can act as an __ to induce IFN responses

A

adjuvant

25
Q

What is gene editing?

A

A type of genetic engineering in which DNA is inserted, deleted, modified or replicated at a specific location in the genome

26
Q

Gene editing tools can induce __ in the genome that are subsequently repaired

A

double-stranded breaks

27
Q

Non-homologous end joining?

A

An error prone repair mechanism that results in uncontrolled but predictable indels

28
Q

What is homology directed repair?

A

A precise repair mechanism triggered in the presence of homologous donor DNA template that results in insertion of the template into genomic DNA

29
Q

Biggest breakthrough in gene editing

A

CRISPR (clustered regularly interspaced short palindromic repeats)

30
Q

2 nuclease domains of Cas9 that cleave DNA

A

RuvC- and HNH-like domains

31
Q

Cas9 nucleases are guided by __ to generate predominantly blunt-end DSBs

A

single guide RNA (sgRNA)

32
Q

sgRNA recognises a very specific sequence called __

A

PAM

33
Q

What is base editing?

A
  • Mutated Cas9 that creates single-stranded breaks (repaired more easily)
  • DNA deaminase allows for point mutations (less dangerous compared to CRISPR)
34
Q

Prime editing involves Cas9 that also creates a single-stranded break, coupled with __

A

reverse transcriptase

35
Q

Ex vivo gene editing being done for __ disease

A

sickle cell disease

PT4024 (11 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions